Donald Trump asked Volodymyr Zelenskyy whether Ukraine could strike Moscow, an inquiry that the White House says was merely a question but one that came hours after he voiced frustration at Russian President Vladimir Putin’s refusal to accept a ceasefire in the war.During a July 4 phone call with the Ukrainian president, Trump quizzed Zelenskyy about whether Ukraine could hit the Russian capital and St Petersburg if given US long-range weapons, according to a person briefed about the conversation. Zelenskyy replied that it could if the US provided the weapons, the person said.Asked about the details of the call, which were first reported by Financial Times, White House press secretary Karoline Leavitt said: “President Trump was merely asking a question, not encouraging further killing. He’s working tirelessly to stop the killing and end this war.” The conversation took place a day after Trump said he was “very disappointed” by a phone call with Putin, in which the Russian leader insisted he wouldn’t back down on his war aims.Ukraine has successfully targeted Moscow with drones in the past, but the long-range missiles provided by its allies so far have lacked the capabilities to reach the city.Details of the discussion emerged a day after Trump pledged fresh weapons supplies to Kyiv that would be paid for by Nato allies, mainly from Europe, and threatened harsh penalties targeting Russian oil sales if Putin doesn’t end the war on Ukraine within 50 days.Oil declined for a second day as traders doubted Trump’s plan would pose a meaningful obstacle to Moscow’s energy exports. Trump’s move to raise pressure on Putin came after months of unsuccessful diplomacy aimed at persuading Russia to halt the war and negotiate a peace deal. Instead, Russia has intensified its drone and missile attacks on Ukrainian cities in recent weeks.Trump told BBC in an interview on Monday that he was “disappointed” in Putin, but not “done with him”. The US president didn’t explain how the proposed “secondary tariffs” would work, but he has used the term in the past to describe duties imposed on countries for trading with American adversaries. The threats echo punishment spelled out in a bipartisan bill in Congress that would impose 500% tariffs on countries that buy Russian oil and gas such as China and India.