As the Trump administration announced plans Wednesday to remove thousands of U.S. troops from Germany, Sen. Mitt Romney criticized that as a huge mistake that hurts American allies and helps adversaries.

The Utah Republican issued a statement that the move “is a grave error. It is a slap in the face at a friend and ally when we should instead be drawing closer in our mutual commitment to deter Russian and Chinese aggression.”

Germany is a hub for U.S. operations in the Middle East and Africa.

Romney, the 2012 GOP presidential nominee, added, “It is a gift to Russia coming at a time when we just have learned of its support for the Taliban and reports of bounties on killing American troops. The move may temporarily play well in domestic politics, but its consequences will be lasting and harmful to American interests.”

Romney has been fighting the move since Trump earlier proposed it.

The senator had introduced an amendment to the annual defense authorization bill to limit the use of funds to reduce U.S. troops in Germany — but amid political maneuvering, it never came to a vote before the Senate passed its version of the bill.

A House version of that bill contains provisions designed to limit troop withdrawal, and still must be reconciled with the Senate version.

The move is another example of Romney challenging the president from his own party when he believes it is warranted — after he earlier was the only Republican senator to vote to impeach Trump.

However, Rep. Chris Stewart, R-Utah, a member of the House Intelligence Committee, tweeted on Wednesday that he supports Trump’s action.

“Reducing the heavy concentration of troops in Germany enhances our defense posture,” he wrote. “Repositioning U.S. troops East will clearly enhance Russian deterrence.”

He added, “I hope that members of Congress will take time to really understand this issue.”

On Wednesday, The Associated Press reported that the Pentagon will bring home about 6,400 troops from Germany and shift about 5,400 to other countries in Europe. The plan leaves about 25,000 troops in Germany.

It was spurred by Trump’s announced desire to pull troops out of Germany, at least in part due to its failure to spend enough on defense. Also, it is tied to Trump’s announced desire to increase U.S. troops in Poland.

The Associated Press said the decision to keep nearly half the forces in Europe is a clear move by the Pentagon to assuage allies by avoiding the complete withdrawal of 10,000 troops out of the region. And by spreading forces into the east, it sends a message to Russia that the United States is not reducing its commitment to the region and remains ready to protect Eastern Europe from any Moscow aggression.

Sen. Jim Inhofe, the Republican chairman of the Senate Armed Services Committee, has voiced support for the plan, while also acknowledging it will take “months to plan, and years to execute.” He was briefed on the issue last week, and issued a statement saying the “concept for realigning U.S. military posture in Europe” is sound.

Trump has branded Germany “delinquent” for failing to meet a NATO goal set in 2014 for members to halt budget cuts and move toward spending at least 2% of gross national product on defense by 2024. And he asserted that the Germans had long shortchanged the United States on trade and defense, declaring that “until they pay” more for their own defense, he will reduce U.S. troops.

Overall, the U.S. has about 47,000 troops and civilian personnel in Germany, spread out across a number of bases, headquarters and smaller installations. Most of the 35,000 active-duty forces are in a handful of larger Army and Air Force bases including Ramstein Air Base, a hub in the region. There also are 2,600 National Guard and Reserve forces in Germany, and almost 12,000 civilians working for the services or for the Defense Department.

Clarification: July 29, 2020, 3:55 p.m. This story has been updated to add the comments of Rep. Chris Stewart, R-Utah.