Evan Vucci/AP

Acting Chief of Staff Mick Mulvaney, speaking to reporters today, said part of the reason why President Trump withheld money to Ukraine was "the corruption related to the DNC server."

"The look back to what happened in 2016 certainly was part of the thing that he was worried about in corruption with that nation. And that is absolutely appropriate," he said.

Mulvaney said the Trump administration does "that all the time with foreign policy."

He said Trump also dislikes sending money overseas.

"President Trump is not a big fan of foreign aid. Never has been, still isn't. He doesn't like spending money overseas, especially when it's poorly spent. And that is exactly what drove this decision," Mulvaney said.