Prime minister is ‘hellbent’ on fighting any contest, even if his future may be out of his hands, sources say

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Keir Starmer’s closest aides are “war-gaming” how to win a leadership contest ahead of Andy Burnham’s much-anticipated return to Westminster if he wins the Makerfield byelection, the Guardian understands.

Downing Street sources said the prime minister had taken the last fortnight to think seriously about his future but was now “hellbent” on fighting any contest. His team is working through various scenarios, including sacking ministers who publicly support Burnham.

In a wide-ranging interview, an upbeat Ukrainian president also discusses Donald Trump, King Charles, and how Kyiv is prepared to share its experience of drone warfare with the west

Sitting down with the Guardian in London, Volodymyr Zelenskyy seems cheerful. More than four years after Vladimir Putin’s full-scale invasion, he believes Europe’s biggest war since 1945 appears to be slowly turning in Ukraine’s favour. The military situation is the most promising it has been for Kyiv for two and a half years, Zelenskyy says. “We can’t say Russia is losing this war. But we can say they are losing the initiative each day, day by day,” he insists.

Over the past week the Kremlin has suffered a series of setbacks. Long-range Ukrainian drones have hit Putin’s home city of St Petersburg, setting fire to oil terminals and sending smoke billowing above the skyline. Similar attacks have crippled occupied Crimea. A key supply road is littered with burning lorries and tankers and the peninsula seized by Russia in 2014 is experiencing severe fuel shortages.

Exclusive: Ukrainian leader says he has ‘a very good relationship’ with British monarch, who has supported his country

• Zelenskyy hopes Reform UK councils will allow Ukraine flags to be flown again

Volodymyr Zelenskyy has revealed that he plans to invite King Charles on a state visit to Ukraine as early as this year, which would make him the most senior royal to travel to Kyiv since Russia’s full-scale invasion.

The Ukrainian president said he had a close relationship with the king, whom he has met on numerous occasions, including when he gave a public show of support after Zelenskyy’s explosive visit to the White House last year.

Exclusive: Ukrainian president says ‘small mistake can break a big friendship’ in wide-ranging interview with Guardian

Volodymyr Zelenskyy has said the decision by some Reform UK councils to take down the Ukrainian flag was the kind of “small mistake that can break a big friendship”, as he underlined the significance of strong bilateral relations.

The Ukrainian president tempered his rare foray into UK domestic politics by stressing how much the two countries “need each other” in the battle against Russia, which he said posed a threat not only to Ukraine but to Britain too.

Keir Starmer says he will fight on as prime minister, but behind the scenes he is said to be thinking about his legacy. He’s talking this week about tech companies and the shape of a social media ban, but he is also focussed on resetting the UK’s relations with EU and defence. Pippa and Kiran discuss what his legacy might be and the role Andy Burnham has to play