Russia's Wagner mercenary group has started moving its forces out of the Ukrainian city of Bakhmut, its founder Yevgeny Prigozhin said on Thursday.

"We are withdrawing the units from Bakhmut. From today at five in the morning, May 25 until June 1, most of the units will rebase to camps in the rear. We are handing our positions to the military," he said in a video posted on Telegram.

Prigozhin announced the capture of Bakhmut on Saturday after the longest and bloodiest battle of the war. He said his fighters would pull out by June 1 and regular Russian troops would move in to replace them.

According to Ukrainian Deputy Defense Minister Hanna Maliar, Russia has replaced its Wagner private military units with regular soldiers on the outskirts of Bakhmut, but the group's fighters remain inside the devastated city.

The Ukrainian military said it still controls some objects on the outskirts of Bakhmut.

On Wednesday, Prigozhin said that around 10,000 prisoners he recruited to fight in Ukraine have been killed on the battlefield.

Here are some of the other developments concerning Russia's war in Ukraine on Thursday, May 25:

Russia to deploy 'non-strategic' nuclear weapons in Belarus

Belarus's autocratic leader Alexander Lukashenko has announced the signing of a decree that would allow Russia to deploy tactical, shorter-range nuclear weapons in the country.

Lukashenko's statement stressed they were "non-strategic" nuclear weapons, so not longer-range and higher-yield bombs.

The Russian TASS news agency cited on Thursday Lukashenko as saying that the movement of the weapons was already underway, after Russian President Vladimir Putin signed the decree.

The agreement allows Moscow to store warheads at a special facility in Belarus.

Russia would maintain control of the weapons, as per the deal, which formalizes an earlier agreement between the two state leaders and allies.

Previously in March, Putin announced the intention to deploy tactical nuclear weapons in Belarus.

Both Moscow and Minsk justified the deal as a response to what they perceive as Western hostility, amid Russia's ongoing war in Ukraine.

Last year, Minsk allowed Moscow to use its territory for launching attacks on Ukraine.

Ukrainian counteroffensive 'underway for days' — Zelensky advisor

Kyiv's long-awaited counteroffensive against Russian troops is underway, according to presidential advisor Mykhailo Podolyak.

"The counteroffensive has been going on for days," he said during an interview with Italian television on Wednesday evening.

"This is an intense war along a 1500-kilometer [9,300-mile] border. Our actions have already begun," Podolyak added.

At the same time, the adviser to President Volodymyr Zelenskyy denied that Ukraine was involved in the attacks in the Russian region of Belgorod.

The advisor went on to say that Ukraine did not want to attack Russian territory.

Addressing the Italian journalist, he said: "We are using the weapons you gave us to destroy Russian positions in Moscow-occupied territories, Donbas and Crimea included." 

However, he said the Belgorod offensives were dangerous for Russian President Vladimir Putin.

"What is happening in the border region is a shock to Putin and will lead to his end."

Podolyak added that Ukraine's airspace could "finally" be closed if F16 fighter jets were delivered.

Ukraine, Russia swap prisoners in PoW exchange

Andriy Yermak, head of Ukraine's presidential administration, said 106 service personnel taken prisoner by Russia have been released in the latest prisoner exchange between the two sides.

Yermak reported the release of "servicemen from the Bakhmut direction — 8 officers and 98 soldiers and sergeants." 

"They've fought for Bakhmut and performed a feat that prevented the enemy from advancing further into our East. Each of them is a hero," he wrote on Twitter.

Russia has not yet revealed how many people it has brought back as part of the recent POW exchange.

EU extends tariff suspension for imports from Ukraine

The European Union agreed to suspend restrictions on imports from Ukraine for a further year after warding off an import ban on grain imposed by some EU nations. The European Parliament has already backed the tariff suspension proposal.

The EU lifted tariffs and other restrictions for an initial 12 months in June 2022. The suspension of all duties has led to complaints from farming groups, culminating in Poland and Hungary banning some Ukraine grain imports in April. The countries became transit routes for Ukrainian grain that could not be exported through its Black Sea ports.

Even before Russia's invasion in February last year, Ukraine had been benefiting from the elimination of the vast majority of EU tariffs, in some cases with transition periods, under the EU-Ukraine free trade agreement applied since 2016.

However, up until 2022, the EU had retained minimum prices for fruit and vegetables and tariffs and quotas on other sensitive farm products, such as meat, dairy, sugar and some cereals.

Finland to send more weaponry to Ukraine

Helsinki says it will send extra military gear to Ukraine, including anti-aircraft weaponry and ammunition a combined cost of 109 million euros ($120 million).

"For operational reasons and in order to ensure the safe delivery of assistance, no further details are provided on the exact content, method or timetable of assistance," the Finnish government said.

Kyiv air defense repels overnight drone attack

Russian forces carried out overnight drone attacks on Kyiv, officials said on Thursday, continuing a monthlong campaign of air strikes against the Ukrainian capital.

Military chiefs said Kyiv's air defenses destroyed all 36 drones during the three-hour air attack, the 12th this month.

Serhiy Popko, head of the city's military administration, said in a message on Telegram that Russia "again attacked Kyiv from the air."

"The attack was massive," the statement added. "The enemy continues to use attack tactics in several waves, with intervals between groups of attacking drones."

He added that "all detected air targets moving in the direction of Kyiv were destroyed" by Ukrainian air defense systems.

The attacks were carried out using Iranian-made Shahed drones, the statement added, citing preliminary information.

In his nightly video address on Wednesday, Ukrainian President Volodymyr Zelenskyy urged Iranians to reconsider the supply of deadly drones to Russia in order to stop their slide into "the dark side of history."

"The simple question is this: what is your interest in being an accomplice to Russian terror?" Zelenskyy said in his address.

"What is the benefit to Iran of such cynical killing? By Russian hands, but with your weapons," he added. "Your Shaheds, which terrorize Ukraine every night, mean only that the people of Iran are being driven deeper and deeper into the dark side of history."

Iranian-made Shahed drones supplied to Moscow have played a major role in Russia's attacks on cities and infrastructure, although Zelenskyy said Kyiv's air defenses were now skilled at downing them. He said about 900 of 1,160 drones aimed at Ukrainian targets were shot down.

Russia has boosted its military cooperation with Iran since invading its neighbor in February 2022. Iran initially denied supplying Shahed drones to Russia but later said it had provided a small number before the conflict began.

Russia expels five Swedish diplomats

Moscow said it would expel five Swedish diplomats in what it said was a retaliatory measure for Sweden's "confrontational course" in relations with Russia.

The Russian Foreign Ministry said it was responding to the expulsion of five of its diplomatic staff from Sweden last month, which it called an "openly hostile step."

The ministry added that Russia would withdraw its consent to the activities of the Consulate General of Sweden in St. Petersburg from September. It also said it would close its Consulate General in Gothenburg.

Relations between the two countries have worsened since Sweden last year announced its intention to join NATO following Russia's invasion of Ukraine. The Russian statement said ties had "reached an unprecedented low."

Russia detains Ukrainians over power station plots

Russia's security service FSB announced the arrest of two Ukrainians who it said had planned to target nuclear power plants in the country.

"A sabotage group from the Ukrainian foreign intelligence service... tried to blow up some 30 power lines of nuclear power plants in Leningrad and Kalinin" in early May with the aim of stopping the nuclear reactors at the plants, Russian news agencies quoted the FSB as saying in a statement.

The attacks were due to take place on the eve of the May 9 anniversary of victory over Nazi Germany, the FSB said.

It did not specify when the men had been arrested but said two Russian accomplices had also been detained.

The Leningrad station, Russia's biggest atomic power plant, is located in the Gulf of Finland, not far from St Petersburg. The Kalinin nuclear power station lies some 350 kilometers (217 miles) north of Moscow.

Russia, Belarus sign document on tactical nuclear weapon deployment

The defense ministers of Russia and Belarus signed a document on the deployment of Russian tactical nuclear weapons in Belarus, Russian state-owned news agency TASS reported.

Separately, Russian media reported that Russian Defense Minister Sergei Shoigu said that the West was waging an "undeclared war" against Russia and Belarus.

Russia and Belarus, which are close allies over the conflict in Ukraine, agreed earlier this year to deploy part of Moscow's tactical nuclear arsenal in Belarus.

Six drones shot down in Crimea, no casualties

Six drones were downed or blocked overnight in Russian-annexed Crimea, the region's Moscow-appointed governor said.

"During the past night, six drones were shot down or blocked ... in different parts of Crimea," Sergei Aksyonov wrote on Telegram, adding "there were no victims or injured." 

The incident comes after Moscow used jets and artillery against an armed group that allegedly crossed into Russia's Belgorod region from Ukraine. It was the most serious attack on its soil since the start of the war.

Earlier this month, Russian authorities claimed they had thwarted missile and drone attacks on Crimea.

South Korean ammunition headed to Ukraine via US — report

Hundreds of thousands of South Korean artillery rounds are on their way to Ukraine via the United States, after Seoul's initial resistance toward arming Ukraine, the Wall Street Journal reported.

Citing unnamed sources, the publication said Seoul had reached a "confidential arrangement" with Washington to transfer the shells to the United States to be delivered to Ukraine, after Washington asked its Asian ally last year for artillery support.

Jeon Ha-kyu, spokesperson at South Korea's Defense Ministry, said on Thursday that it had been in talks with the Pentagon about ammunition exports but that there were "inaccurate parts" in the WSJ report, declining to give details.

A US ally and major producer of artillery ammunition, South Korea had so far ruled out sending lethal aid to Ukraine, citing business ties with Russia and Moscow's influence over North Korea, despite mounting pressure from Washington and Europe to supply weapons.

US approves $285 million sale of air defense system to Ukraine

The United States has announced the $285 million (€265 million) sale of a NASAMS air defense system and related equipment to Ukraine as Kyiv seeks to boost protection against Russian strikes.

"Ukraine has an urgent need to increase its capabilities to defend against Russian missile strikes and aircraft," the US Defense Security Cooperation Agency said in a statement. "Acquiring and effectively deploying this capability will enhance Ukraine's ability to defend its people and protect critical national infrastructure."

The agency also said the sale will support US foreign policy national security goals by "improving the security of a partner country that is a force for political stability and economic progress in Europe."

The sale would not require any additional US government employees or contractors to be assigned to Ukraine, the statement added. The State Department approved the sale, and the DSCA on Wednesday provided the required notification to Congress, which still needs to sign off on the transaction.

Countries including the US that are supporting Ukraine in its battle against invading Russian forces have donated tens of billions of dollars' worth of military equipment to Kyiv, but this transfer would be a sale.

More DW content on Russia's war in Ukraine

Hundreds of Russian citizens are fighting as volunteers on the Ukrainian side, according to media reports. Who are they and what are their hopes for the future of Russia?

dh/nm (AP, AFP, dpa, Reuters)