Kyiv, Ukraine - The US Secretary of Defense, 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 – formally known as Twitter – 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 Defense Minister Rustem Umerov, US media traveling with the secretary reported.

His visit to Kyiv comes in the waning months of the Biden administration and with all eyes on the dead-heat race for the White House.

Democratic Vice President Kamala Harris has vowed to continue military aid to Ukraine should she win on November 5, while her Republican rival Donald Trump has expressed antipathy for further support.

The US has been the largest military and financial backer of Ukraine since the start of the all-out Russian invasion in February 2022.

Russian forces have made slow but steady territorial gains in eastern Ukraine. Zelensky has pressed his allies in the West to allow Ukraine to strike targets deep inside Russia, but to no avail.