Volodymyr Zelensky called for “strong” ties with Washington on Thursday, as he met US envoy Keith Kellogg in Kyiv a day after Donald Trump branded the Ukrainian leader a “dictator”.AdvertisementTensions between Zelensky and Trump over the US president’s outreach to Moscow have exploded this week in a series of escalating barbs traded in press conferences and on social media.The United States is Ukraine’s most important financial and military backer, but the US president has rattled Kyiv and its European backers by opening talks with Moscow they fear could end the war on terms that reward Vladimir Putin.The row has turned...