US President Joe Biden made an unannounced visit to Kyiv on Monday in a show of support ahead of the anniversary of the Russian invasion, promising President Volodymyr Zelensky that Washington would support Ukraine for as long as it takes. When Biden visited Kyiv, air raid sirens wailed over the Ukrainian capital, although there were no reports of Russian missiles or airstrikes. Reporting by Gulliver Cragg of FRANCE 24 from Kyiv, Ukraine.