British Ambassador to the U.S. Karen Pierce called on President Vladimir Putin to withdraw from Ukraine Tuesday and allow humanitarian aid to be delivered, reminding co-hosts Bill Hemmer and Dana Perino on "America's Newsroom" that Ukraine did not attack or provoke Russia and ending the war is in Putin's hands.

PENTAGON'S KIRBY SAYS 'SINGULAR OBJECTIVE' AGAINST RUSSIA IS PROTECTING UKRAINE 'SOVEREIGNTY'

AMB. KAREN PIERCE: It ought to end with Russia declaring a cease-fire and then withdrawing and allowing humanitarian assistance to get to the Ukrainians who Russia has injured with its shelling. I think we have to bear in mind this is a conflict provoked entirely by Russia. Ukraine did not attack Russia. Ukraine did not provoke Russia. NATO didn't attack. NATO didn't provoke. This is entirely down to Russia and to President Putin. So it's in their hands. They need to call the cease-fire, and they need to start withdrawing.

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