Polish Foreign Minister Radoslaw Sikorski said on Monday he hoped U.S. President Donald Trump and his administration would see that Vladimir Putin was "mocking their goodwill" following Moscow's deadly missile strike on the Ukrainian city of Sumy.

Steve Witkoff made an unannounced trip to St. Petersburg as talks on the war in Ukraine appear to have stalled.

Russia's missile attack on Sumy drew widespread criticism from international leaders with French President Emmanuel Macron claiming that Russia was 'undermining the diplomatic efforts made by President Trump.