The US secretary of defence, Lloyd Austin, arrived in Ukraine on Monday for an unannounced visit, his fourth since assuming the position in 2021 and at a precarious moment for the country. Austin wrote on X that his trip was meant to demonstrate “that the United States, alongside the international community, continues to stand by Ukraine.” Austin will meet with Ukrainian President Volodymyr Zelensky and Defence Minister Rustem Umerov, US media travelling with the secretary reported. His visit to Kiev comes in the waning months of the Biden administration and with all eyes on the dead-heat race…