Volodymyr Zelenskiy confirms ‘counteroffensive and defensive actions’; president says his generals are in ‘positive mood’ but gives no more details

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Putin and Zelenskiy tussle over Ukraine’s counteroffensive narrative; water levels begin to recede in flooded regions near destroyed Kakhovka dam

• See all our Russia-Ukraine war coverage

Russian president Vladimir Putin said Ukraine had begun its counteroffensive against Russian troops but that efforts “so far have failed” after Moscow said it repelled several Ukrainian assaults. However, Ukrainian president Volodymyr Zelenskiy made no formal announcement of specific developments on the battlefield, but praised the “heroism” of his country’s soldiers fighting “tough battles”.

Water levels are gradually receding in parts of southern Ukraine that were flooded after the destruction of the Kakhovka dam, according to officials. Meanwhile, evidence is growing that the dam was blown up after seismic data showed there was a blast at the site in the early hours of Tuesday. Norsar, the Norwegian Seismic Array, said signals from a regional station in Romania pointed to an explosion at 2.54am. Norsar did not draw conclusions on who was responsible.

The US said Russia appeared to be deepening its defence cooperation with Iran and had received hundreds of one-way attack drones that it is using to strike Ukraine. Citing newly declassified information, the White House said the drones were built in Iran, shipped across the Caspian Sea and then used by Russian forces against Ukraine.

The Wagner group has been accused of stoking “anarchy” on Russia’s frontlines after one of the Kremlin’s military commanders claimed Yevgeny Prigozhin’s mercenaries had kidnapped and tortured his soldiers during the battle for Bakhmut. In a video posted online, Lt Col Roman Venevitin also accused Wagner soldiers of stealing arms, forcing mobilised soldiers to sign contracts with Wagner, and attempting to extort weapons from the Russian defence ministry in exchange for releasing kidnapped soldiers.

Iceland announced it would suspend work at its embassy in Russia as of 1 August, the first country to do so, and asked Russia to limit its operations in Reykjavik. “The current situation simply does not make it viable for the small foreign service of Iceland to operate an embassy in Russia,” foreign minister Thordis Gylfadottir said.

Russia will start deploying tactical nuclear weapons in Belarus after the facilities are ready on 7-8 July, Putin told his Belarusian counterpart Alexander Lukashenko on Friday in a meeting in Sochi, Russia.

Nato allies on Friday condemned Russia’s decision to withdraw from the treaty on conventional armed forces in Europe (CFE).

Hungary said on Friday it had received a group of Ukrainian prisoners of war from Russia, a release that Ukraine welcomed while expressing concern that it had not been informed.

Volodymyr Zelenskiy has thanked Joe Biden for his $2.1bn (£1.6bn) security assistance package. In a tweet, Zelenskiy said the contribution is “more important than ever” since the Kakhovka dam collapse.

The Japanese prime minister, Fumio Kishida, told Zelenskiy on Friday that Japan will offer emergency humanitarian aid worth about $5m (£3.9m) after the destruction of the Nova Kakhovka dam, a Japanese government spokesperson has said.

Ukraine’s domestic Security Service (SBU) said on Friday it had intercepted a telephone call proving a Russian “sabotage group” blew up the Kakhovka hydroelectric station and dam in southern Ukraine. A one-and-a-half minute audio clip on its Telegram channel of the alleged conversation featured two unidentified men who appeared to be discussing the fallout from the disaster in Russian. One of the men said “Our saboteur group is there. They wanted to cause fear with this dam. It did not go according to the plan. More than they planned.”

The Kremlin on Friday accused Ukrainian forces of killing civilian victims of flooding caused by the collapse of the Kakhovka dam in southern Ukraine in repeated shelling attacks, including one pregnant woman. Kremlin spokesperson Dmitry Peskov called the purported attacks “barbaric”. Russia did not provide any evidence to back up its claims.

Russian deputy prime minister Marat Khusnullin said on Friday that Crimea’s water supply will not be affected by the destruction of the Kakhovka dam, and the peninsula had enough water reserves for 500 days. A canal from the destroyed reservoir fed drinking water to the peninsula. Kyiv cut access to the canal in 2014, after Russia illegally seized Crimea and claimed to annex it.