Russia is sending weapons to the Taliban in Afghanistan through Iran, retired Gen. Jack Keane said this morning on "America's Newsroom."

Defense Secretary James Mattis said in Afghanistan yesterday that the United States will "engage diplomatically" with Russia, but said "we're going to have to confront Russia" if violations of international law are occurring. 

"Any weapons being funneled here from a foreign country would be a violation of international law," he said.

Keane, a Fox News military analyst, explained this morning that the Russians are working with Iran to undermine U.S. forces in the country. 

"There's a lot of arms. ... It's assault rifles, rocket-propelled grenades, sniper rifles, mortars and explosive devices. There is a lot of arms going to the Taliban," said Keane, adding that Tehran and Moscow reject the "permanence" of U.S. forces in the country.

He said the end goal for the Kremlin is to weaken popular support for the U.S. efforts in Afghanistan, hoping the United States will give up and "go home."

Keane said the Trump administration must call out and confront Vladimir Putin, which the previous administration failed to do. 

Watch the discussion above, including Keane's thoughts on the North Korea tensions.

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