Sen. Ben Sasse (R-Neb.) says Congress needs to get to the bottom of what President Trump was told about Russia offering bounties to Taliban militants to kill coalition troops in Afghanistan, calling for a “proportional response” from the U.S.

Sasse, a member of the Senate Intelligence Committee, told reporters Monday that explosive reports over the weekend that Russia’s military intelligence agency, the GRU, offered bounties on U.S. service members should be investigated by Congress and that the effort should transcend the “short-term politics” that usually dominate Capitol Hill.

“I’ve been hearing from military families in Nebraska constantly for the last 36 hours, and they’re livid,” he said. “This is a story about the targeting of American men and women in uniform. This is about putting crosshairs on the backs of people who are fighting for our freedom. This is not about short-term politics.”  

Sasse said Congress “is broken” and needs to pull together to “get to the bottom of two questions.”

“Who knew what when inside the administration? Did the commander in chief know? If not, why the heck not? What’s going on in that process?” he said.

Sasse said the second question is “What is our plan to impose proportional response on our enemies in this battle?”

He said such a response “would mean Taliban and GRU agents in body bags.”

He called on colleagues to put aside their partisan differences and investigate the intelligence claims, which Trump said Monday U.S. officials did not find “credible.”

“This institution needs to be really serious about the oversight we do,” he warned.

Sasse said he spoke with Trump on Sunday evening and with members of the U.S. intelligence community on Sunday and Monday on the subject.

“I think that it should be clear that we are deadly serious about this topic because it’s a deadly serious topic. Most of the families that have contacted me are not the kinds of people who do the 24-hour news cycle,” he said.

Sasse joined lawmakers from both sides of the aisle in calling for a complete explanation from the administration. 

“Right now, I don’t think the messages that we’re hearing coming out of the White House are serious enough about the magnitude of the problem,” he said.

The New York Times first reported on Friday that American intelligence officials had concluded that the Russian military intelligence agency had offered bounties to militants to kill coalition troops.

The bombshell allegation received little response from the White House on Friday and Saturday.

Trump finally broke his silence Sunday morning, claiming on Twitter that “nobody briefed or told me.” He said neither Vice President Pence nor White House chief of staff Mark Meadows was briefed either.

The Washington Post reported Sunday that intelligence assessments concluded the Russian bounties led to the deaths of U.S. troops.

Trump tweeted on Sunday evening that the intelligence community didn’t find the allegations to be credible.

“Intel just reported to me that they did not find this info credible, and therefore did not report it to me or @VP. Possibly another fabricated Russia Hoax, maybe by the Fake News @nytimesbooks, wanting to make Republicans look bad!!!” Trump wrote.

Sasse isn’t satisfied with those answers.

“Who knew what when? Did the commander in chief know? And if he didn’t, how in the hell didn’t he know?” he said.

When asked if he would support legislation sponsored by Sen. Bob Menendez (N.J.), the top-ranking Democrat on the Senate Foreign Relations Committee, placing new sanctions on Russia, Sasse said, “I’m looking for something more urgent than that.”

“We should be talking about GRU and Taliban agents in body bags,” he said.