U.S. Secretary of State Mike Pompeo says that it is U.S. President Donald Trump who chose to send defensive weapon systems to Ukraine.

"As for appropriate action, I've watched the president engage with the Ukrainian leadership. I listened to conversations. I remember the previous administration refusing to send defensive weapon systems to Ukraine. This president has chosen to do that not once, not twice, but now three times, so that the Ukraine people could fight back against the overtaking of southeast Ukraine. You remember, it was the previous administration that allowed Vladimir Putin to take one fifth of the Ukrainian country," he told John Roberts of Fox News Sunday on September 22.

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What is more, he says talks on military aid to Ukraine were always "100 percent appropriate."

"I've watched this president evaluate how and when and to the extent we should provide support to Ukraine, both defense assistance and other foreign assistance, we've been at the center of that. Those conversations have always been 100 percent appropriate, 100 percent lawful, and 100 percent ensuring that the American taxpayers were protected, that we put those resources to good use and we've got good outcomes in Ukraine when we used American taxpayer dollars to support the Ukrainian leadership – every single time," he said.

He also confirmed a meeting between Trump and his Ukrainian counterpart Volodymyr Zelensky this week. "We're going to see President Zelensky this week," he said.