Russian forces break through Ukraine frontline days before Putin-Trump summit

Vladimir Putin's troops have reportedly staged a sudden breakthrough on the Ukrainian frontline - just days before the Russian leader is due to meet the US President for critical peace talks.

The unexpected push took place near the coal-mining town of Dobropillia and marks the most dramatic movement on the front line so far this year, possibly handing Putin a strategic advantage at the negotiating table on Friday. Reports claim around 100,000 Russian troops have moved at least 10km north in two separate thrusts over recent days, part of an ongoing campaign to capture the whole of the Donetsk region. Forces are also said to have pushed towards three villages in a section of the front near Kostyantynivka and Pokrovsk.

Ukraine's DeepState authority warned: "The situation is quite chaotic, as the enemy, having found gaps in the defence, is infiltrating deeper, trying to quickly consolidate and accumulate forces for further advancement." It comes after Putin warned of a nuclear war after unleashing another night of hell on Ukraine.

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Military sources say the latest assault relied on small sabotage and infantry groups to break through. Ukrainian officials confirmed that reinforcements had been sent to the area, and reported that some Russian soldiers had been killed or taken prisoner.

The escalation comes amid diplomatic tension, with Moscow accusing Britain of attempting to disrupt the forthcoming Trump-Putin meeting. The accusation followed comments from Sir Keir Starmer, who insisted the Russian leader could not be trusted. "Peace must be built with Ukraine, not imposed upon it," Starmer said on Monday, as he expressed concern that Kyiv could be left out of the negotiations.

Asked whether he thought Putin could be trusted, the prime minister's official spokesman said the UK supported both Kyiv and the US president's push for peace, but not Moscow. "Never trust President Putin as far as you could throw him, but we obviously will support Ukraine," he said.

"We will obviously support President Trump and European nations as we enter these negotiations. But it is exactly why we’ve been leading this work on the coalition of the willing, because any ceasefire, as I say, cannot just be an opportunity for President Putin to go away, re-arm, restrengthen, and then go again.

"So we're not going to leave it to trust. We’re going to ensure that we’re prepared such that we achieve a ceasefire."