Ukraine said its troops are continuing to make gains moving eastward toward the Russian-occupied Donbas region, setting the stage for a push to potentially recapture parts of Luhansk province.

Ukraine's Luhansk provincial Governor Serhiy Gaidai said Ukrainan troops had retaken the village of Bilohorivka, a suburb 10 kilometers (6 miles) west of the city of Lysychansk, which fell to Russian forces after fierce fighting in July. 

Although the reports could not be independently verified, the capture of Bilohorivka would mean Russia no longer has full control of Luhansk province. Lysychansk was the last Ukrainian city in Luhansk to fall after the Russian summer offensive in the region, which had been touted as a major victory by Moscow.

Gaidai said Ukrainian forces are preparing to take the remainder of Luhansk province from Russian occupiers.

"There will be fighting for every centimeter," Gaidai wrote on Telegram. "The enemy is preparing their defense. So we will not simply march in," he added.  

Meanwhile, Ukrainian President Volodymyr Zelenskyy said Ukrainian troops were gaining ground as Russian soldiers abandoned territory.

"The occupiers are clearly in a panic," Zelenskyy said in a televised address late on Monday, adding that he was now focused on "speed" in liberated areas.

On Tuesday, Russian-installed officials in Luhansk claimed that a Ukrainian strike on Krasnorichenske, a village some 30 kilometers (19 miles) north of Lysychansk, killed seven civilians. 

Here's a roundup of some other key developments on September 20 regarding Russia's invasion of Ukraine 

West decries Russia's plans to hold referendums in Ukraine

On Tuesday, Russia-backed separatists in the self-declared Luhansk People's Republic (LPR) said they will hold a referendum on joining Russia between September 23-27, according to Russia's TASS news agency.

Shortly thereafter, the neighboring Donetsk People's Republic (DPR) said it would also stage a similar referendum on the same dates.

But Western nations were quick to dismiss the legitimacy of the upcoming ballots.

US President Joe Biden's national security adviser Jake Sullivan said Washington "will never recognize Russia's claims to purportedly annex any parts of Ukraine. And we will never recognize this territory as anything other than a part of Ukraine. We reject Russia's actions unequivocally."

Sullivan called the referendum proposals "an affront to the principles of sovereignty and territorial integrity that underpin the international system," adding it was clear they would be manipulated by Russia.

While attending the UN General Assembly currently taking place in New York, German Chancellor Olaf Scholz said: "It is very, very clear that
these sham referendums cannot be accepted."

French President Emmanuel Macron denounced the pro-Russian separatists' plans, saying any vote for annexation would be legally meaningless.

"I think what Russia announced is a travesty," he told reporters at the UN General Assembly, calling it a "new provocation" that "will have no consequence on our own position."

"The very idea of organizing referendums in regions witnessing war, which are suffering bombings, is the height of cynicism," Macron added.

However, Russia's Foreign Minister Sergei Lavrov said that it is up to the people living in the "respective territories to decide their fate." 

Earlier Tuesday, Russia's former president and current head of the Security Council, Dmitry Medvedev, said it is "essential" that the separatist Donetsk and Luhansk People's Republics hold referendums in order to join the Russian Federation.

Medvedev said on social media that joining Russia would be vital to protecting their interests because it could further justify Russia's use of military force against Ukrainian troops in the Donbas.

The comments come as Vyacheslav Volodin, head of the Duma, said Moscow will support the citizens of the Donbas if they decide to join Russia. Only three countries recognize the two self-declared republics as independent: Russia, Syria and North Korea.

Moscow-backed leaders in the Russian-occupied Kherson region of southern Ukraine and pro-Russia activists in the partly-occupied
Zaporizhzhia region also plan to hold speedy referendums on joining Russia.

In Kherson, the strategic port city that is the westernmost point of Russian-occupied territory in Ukraine, Russian-installed leader Vladimir Saldo urged Moscow to green-light a local referendum so that Kherson could become "a part of Russia, a fully-fledged subject of a united country."

Germany and Slovenia reach agreement over military assistance for Ukraine

Germany and Slovenia have agreed a deal that will see Slovenia send 28 tanks of Soviet-era design to Ukraine, while acquiring 40 modern military trucks from Germany, Berlin's Defense Ministry said, without specifying when exactly the vehicles will be delivered.

The deal foresees Slovenian submitting 28 M-55S tanks to Ukraine and receiving the truck, with five tankers among them.

Germany so far has been reluctant to send Western-designed tanks to Ukraine, arguing that other allies have yet to do so.

Russia reportedly relocating Black Sea subs

Russia has moved a sizable chunk of its Black Sea Fleet submarines away from Crimea in the wake of attacks on Russian naval bases and other military installations in the region, according to the British Ministry of Defense.

The ministry said Russia's Black Sea Fleet command had "almost certainly" relocated KILO-class submarines from Sevastopol, the Crimean port city under Russian control, to the Black Sea port city of Novorossiysk.

"This is highly likely due to the recent change in the local security threat level in the face of increased Ukrainian long-range strike capability," it said in an intelligence update on Tuesday.

UK pledges more military aid for Ukraine

British Prime Minister Liz Truss announced on Tuesday morning that the UK next year would meet or exceed the €2.62 billion pound ($2.63 billion) military aid spent on Ukraine in 2022.

In a statement, Truss' office said this future military support would likely include multiple launch rocket systems to be used on the battlefield.

"My message to the people of Ukraine is this: the UK will continue to be right behind you every step of the way," she said. "Your security is our security."

German foreign minister accuses Russia of attacking core UN values

German Foreign Minister Annalena Baerbock said that this week's United Nations General Assembly, which is due to begin on Tuesday, would not be "like the previous ones."

Ahead of the meeting in New York City, Baerbock said Russia's invasion of Ukraine attacked the principles upon which the UN was founded.

Baerbock said her focus at the meeting would be on "how to deal with and prosecute the horrific crimes committed in Ukraine in Russia's name."

"It takes the United Nations for us to find common solutions to global problems," she added. "No country should have to live in fear of a stronger neighbor attacking it."

Catch up on DW's latest reporting on the war in Ukraine

Ukraine's state energy company Energoatom said a Russian missile landed near the Pivdennoukrainsk nuclear power plant in Mykolaiv region early on Sunday, causing minor damage to some buildings.

DW reports on the threat of a nuclear disaster and other developments from the weekend.

Amid comprehensive sanctions from the West, Russia has attempted a second economic pivot towards Asia.

DW looks at why this new strategy hasn't paid off at recent leaders' conferences.

jsi, zc/wmr (Reuters, AP, AFP, dpa)