Ukrainian President Volodymyr Zelenskiy said on Sunday that a ceasefire with Russia in its more than three-year-old war was possible at any moment and called on Kyiv's allies to apply greater pressure on Moscow to put the measure in place.

Conn., joins 'Fox News Sunday' to discuss Mike Waltz's move from National Security advisor to U.N. ambassador, President Donald Trump working to end the war in Ukraine and border security.