Ukrainian President Volodymyr Zelenskyy said his army is ready to stage a much-awaited counteroffensive against Russia, but warned of mass casualties unless Western allies can provide more military aid.

"A large number of soldiers will die" if Kyiv is not provided with the tools needed to defend against Russian missile strikes, Zelenskyy told the Wall Street Journal in comments published on Saturday.

"Everyone knows perfectly well that any counteroffensive without air superiority is very dangerous," he said.

"Imagine the feeling of a soldier who knows that he doesn't have a roof and he doesn't understand why neighboring countries have one."

In particular, Zelenskyy called for more deliveries of the US-made Patriot air defense system that he said was the only weapon that could defend Ukraine's skies.

"The reality is 50 Patriots will, for the most part, prevent people from dying," he said.

Zelenskyy's comments came as Ukrainian Deputy Defense Minister Volodymyr V. Havrylov praised the effectiveness of Patriot defense systems delivered by the US and Germany earlier this year.

Speaking on the sidelines of Asia's top security conference, the Shangri-La Dialogue in Singapore, Havrylov said Ukraine's existing air defense systems were key to preparing for the counteroffensive.

He said Russia's "primary goal is to stop our counteroffensive and target decision-making centers."

For Russia "it was a huge surprise to find that the effectiveness of (their ballistic missiles) was almost zero against modern air defense systems, which we received from our partners," he added.

Here are some of the other developments concerning Russia's war in Ukraine on Saturday, June 3:

Wagner's Prigozhin hits out at Kremlin factions

Wagner Group chief Yevgeny Prigozhin has accused Kremlin factions of attempting to sow discord between his mercenary organization and Chechen fighters.

In a message posted by his press service, Prigozhin said comments made by Chechen leaders at a Security Council meeting on Friday "were rather provocative, aimed at hurting me and freaking me out."

"Pandora's Box is already open — we are not the ones who opened it," Prigozhin said.

"Some Kremlin tower decided to play dangerous games," he added, using the word "tower" to refer to unidentified factions.

"Dangerous games have become commonplace in the Kremlin towers...they are simply destroying the Russian state."

The former restauranteur who now runs a private army also lashed out at Russian Defense Minister Sergei Shoigu, threatening to deploy his own mercenaries to Belgorod on the Ukrainian border if the military cannot put an end to repeat incursions that guerrilla groups have claimed responsibility for.

"The Ministry of Defense is not in a state to do anything at all as it de facto doesn't exist — it is in chaos," Prigozhin said.

Two Russians dead in Belgorod shelling

Two people have died in the Russian border region of Belgorod in what one official said was Ukrainian shelling.

"Since this morning, the district of Shebekino has been under shelling of the Ukrainian armed forces," said Belgorod Governor Vyacheslav Gladkov on Saturday.

Belgorod was the site of an incursion last month, which Moscow blamed on Kyiv.

Ukrainian officials denied any responsibility and pointed to Russian guerrilla groups that later claimed responsibility for the attacks.

Zelenskyy orders shelter probe after deaths

Zelenskyy told his government on Friday night to remedy problems with air-raid shelters in the capital, Kyiv, as Russia continues heavy missile attacks on the city.

His comments on the shelters in his nightly address come after three people, including a 9-year-old child, were killed by missile debris after reportedly being unable to access a locked shelter. Police have detained four people in an investigation into the deaths.  

Zelenskyy said Kyiv residents were reporting that there were too few shelters, that they were sometimes locked and that access to them was sometimes difficult.

He said that bunkers were entirely lacking in some city districts.

"This level of negligence in the city cannot be justified," Zelenskyy said, adding he had told the strategic industries minister and the interior minister to conduct a "full audit of bomb shelters."

Zelenskyy and Kyiv Mayor Vitali Klitschko, who have clashed before, appear to be trading blame over the shelter issue, with Klitschko saying allies of the president are responsible for shortfalls.

The prosecutor's office in Kyiv said it had joined with police to investigate the situation and that it was also looking into possible misappropriation of funds earmarked for repairing the shelters.   

Kyiv has experienced six consecutive nights and one day of bombing by Russian forces in this week alone. Most missiles and drones have been destroyed by Ukrainian air defenses.

Zaporizhzhia nuclear plant 'extremely vulnerable': IAEA's Grossi

Ukraine and Europe's largest nuclear plant, the Zaporizhzhia Nuclear Power Station, remains in a "highly precarious" situation, having had an insufficient external backup power supply for three months, the head of the International Atomic Energy Agency (IAEA), Rafael Grossi, has warned.

The IAEA said the facility near the southeastern city of Enerhodar now relied on one operational power line for external electricity. The plant needs external power to cool reactors and carry out other vital safety and security measures.

If the line fails, as it did on May 22, the plant would be forced to rely on emergency diesel generators, the IAEA said.

Before the Russian invasion began in February 2022, the plant had four off-site power lines at its disposal.

"The general situation at the site remains highly precarious and potentially dangerous," Grossi said, adding that there was "a need for intensified efforts to ensure a more stable and predictable external electricity supply."

The six-reactor plant has been occupied by Russian forces since March 2022.

Indonesia calls for UN referendum on 'disputed' territory in Ukraine

Indonesia's defense minister has proposed a multi-point peace plan for Ukraine and called on the Shangri-La Dialogue defense summit in Singapore to issue a declaration calling for hostilities to cease.

The plan put forward by Prabowo Subianto called for a cease-fire and a demilitarized zone monitored by UN peacekeepers.  

He also said a UN referendum should be held "to ascertain objectively the wishes of the majority of the inhabitants of the various disputed areas."

"I propose that the Shangri-La dialogue find a mode of ... voluntary declaration urging both Ukraine and Russia to immediately start negotiations for peace," Prabowo said.

His description of Russian-held territories in Ukraine as "disputed areas" is highly questionable under international law and goes against the stance of Ukraine and its allies that Kyiv's territorial integrity has been grossly violated.

Indonesia's president, Joko Widodo, has previously offered his services to both Kyiv and Moscow as a peace broker.

Ukrainian President Volodymr Zelenskyy has proposed a 10-point peace plan that calls on Russia to withdraw all its troops from Ukraine.  

More DW coverage of the Russian invasion

Many Ukrainians are seeking family members who they say are being held prisoner by Russia despite their civilian status, as DW reports.  

Meanwhile, attacks by pro-Ukrainian militants within Russia itself are starting to undermine faith in the country's allegedly insuperable military power.

zc, tj/rs (dpa, Reuters, AFP, AP)