WASHINGTON ― Congress is readying proposals to rebuke President Donald Trump’s plans to pull about 10,000 U.S. troops from Germany amid dissatisfaction with the administration’s rationale for the move and concerns it will weaken NATO.

As Trump confirmed rumored plans to draw down American military personnel levels in Germany in the coming months, a bipartisan group of senators led by Utah Republican Sen. Mitt Romney proposed an amendment to the Senate’s version of the annual defense policy bill that would freeze troop numbers in Germany.

House Armed Services Committee Chairman Adam Smith, D-Wash., said separately Tuesday that the plan seemed strategically unsound and that Congress should block the administration until it makes its case. Legislative action is likely in the House on Wednesday when Smith’s panel marks up the HASC version of the bill.

“It is possible that there is a scenario where repositioning troops out of Germany is in our national security interests. The president has not made that case to date, the [Department of Defense] has not made that case to date, and the president is doing it in a very haphazard manner,” Smith told reporters.

“We need to know what they’re talking about, and it’s appropriate for the moment to say: ‘Yeah, hold up until we know where you’re going and what you’re doing on this.' We don’t think it’s a good idea.”

Trump said during an Oval Office meeting last week with Polish leader Andrzej Duda that the U.S. plans to move some troops from Germany to Poland, and that some troops “will be coming home.” He repeated accusations that Germany has been “delinquent in their payments” to the NATO security alliance.

Though Trump did not disclose the troop numbers involved, White House national security adviser Robert O’Brien said in a Wall Street Journal essay this month that the U.S. will reduce its permanently stationed force in Germany from 34,500 troops to 25,000.

“The Cold War practice of garrisoning large numbers of troops with their families on massive bases in places like Germany is now, in part, obsolete,” he wrote.

The Pentagon has said it is working options with U.S. European Command to meet Trump’s directive. Based on the U.S. agreement with Poland, the U.S. will add a division headquarters, a combat training center, an unmanned aircraft squadron and structure to support an Army brigade that could rotate in and out of the country.

An amendment in the House Armed Serviced Committee to counter that move is likely, according to the top Republican on the panel, Rep. Mac Thornberry of Texas. He’s among a bipartisan group of lawmakers who have expressed concern and deep skepticism about the drawdown plans, which would “benefit the Russians,” “disillusion our allies” and create a logistical headache for the DoD, he said.

“It’s totally unrealistic that you would take thousands of people out of Europe by Sept. 30. Where would you put them? Where’s the housing?” Thornberry told reporters separately on Monday. “Part of the reason I was so concerned about this is I think this idea or this plan ― such as it is ― came from a couple of people in the White House with input really from DoD.”

“There has to be some tie to strategy and our national interest, not issues of personality and so forth,” he said. “I think we will do something [at the HASC markup], and hopefully cooler heads are prevailing.”

The Romney amendment would prevent funds from being used to reduce the number of troops serving in Germany below 34,500 until the defense secretary verifies for Congress the move would not harm NATO, U.S. military operations or military families. There would also have to be assurances the administration consulted allies and that relocating troops would not result in significant costs.

Romney’s co-sponsors include Sens. Lindsey Graham, R-S.C.; Marco Rubio, R-Fla.; Chris Coons, D-Del.; Tim Kaine, D-Va.; and Jeanne Shaheen, D-N.H.

Though the Senate began debate on the 2021 National Defense Authorization Act this week, it’s unclear whether the amendment will receive Senate floor consideration. It’s one of hundreds that have been offered.

Meanwhile, the co-sponsors are cautioning the move would weaken NATO and conflict with U.S. national security interests.

“The withdrawal of U.S. troops from Germany would be a gift to Russia, and that’s the last thing we should be doing,” Romney said in a statement. “We cannot abandon our commitment to our allies, and instead must strengthen our alliances in order to reign in the world’s bad actors and promote the values of freedom and democracy around the world.”

“The administration’s withdrawal plans would inflict lasting damage to our transatlantic relations and harms our national security,” Shaheen said in a statement. “I’m proud to support this bipartisan amendment and hope that the Senate takes this opportunity to send a resounding message to the administration and our allies alike that the United States stands firmly with our allies.”

Leo Shane III of Military Times, and The Associated Press contributed to this report.

Joe Gould was the senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry. He had previously served as Congress reporter.

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