'Where is the evidence?' CNN's Acosta stumps Sarah Sanders after Trump says Clinton colluded with Russia

White House press secretary Sarah Huckabee Sanders refused to explain why President Donald Trump had accused his former rival Hillary Clinton of colluding with the Russian government.

"I was wondering, why did the president involve himself in the Uranium One investigation?" CNN's Jim Acosta asked during a press briefing. "Are you trying to gin up your own Russia investigation to rival the one on Capitol Hill? And where is the president's evidence that Hillary Clinton colluded with the Russians?"

Trump on Friday insisted that it is "commonly agreed" that his presidential campaign did not collude with Russia but that Clinton did.

"The president has pushed for transparency," Sanders said regarding the Uranium One deal investigation. "I know that is probably something new, for a president to actually push for transparency but that's what he's done."

But she refused to answer how Clinton had colluded with Russia.

"How about evidence of collusion," Acosta pressed.

But Sanders tried to move on to another reporter.

"The president made a charge that Hillary Clinton --" Acosta said.

"I think I have addressed that pretty thoroughly," Sanders interrupted. "So I'm saying that I'm calling on your colleague."

"OK, well, you didn't really address that question," Acosta remarked.

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