Congress won’t let the Pentagon close or realign bases in the United States, so the Defense Department has looked to shut down facilities elsewhere: in Europe.

Pentagon officials announced Thursday that they will close or reduce its presence at dozens of facilities across the United Kingdom, Germany, Belgium, The Netherlands, Italy and Portugal, part of a broader consolidation plan that they say would save DOD $500 million annually. The officials stressed that the reorganization would not impact the American military’s ability to respond to a crisis on the continent and in some cases could respond even faster due to better positioning.

The move comes amid increased tension across Europe following Russia’s invasion of Ukraine last year. While the U.S. will consolidate facilities, it still plans to boost rotational deployments of American troops and weapons to Europe for drills with NATO forces, Pentagon officials said. In 2015, the Pentagon plans to spend nearly $1 billion on efforts to boost U.S. training and exercises across the continent.

“Taken together, these decisions on our force presence in Europe will enhance our operational readiness and mission posture at reduced funding levels, all toward the objective of maintaining a strong trans-Atlantic alliance and meeting our common security interest,” Derek Chollet, assistant secretary for international security affairs, said Thursday.

The most notable decision announced Thursday is that the Pentagon is moving U.S. Air Force tankers, intelligence planes and tiltrotor aircraft from RAF Mildenhall in Suffolk, England, to other bases across Europe. The Air Force used the Cold War-era airfield since 1950 when WB-50 Superfortresses arrived at Mildenhall.

A number of aircraft, particularly Air Force KC-135 aerial refueling tankers and special operations CV-22 Ospreys will move from Mildenhall to Ramstein and Spangdahlem air bases, respectively, said Tim Bridges, the deputy assistant secretary for Air Force installations. Both bases are in Germany.

The idea behind the Osprey move is to position them “closer to where the fight is,” Bridges said. All U.S. Air Force personnel are expected to leave Mildenhall around 2019, he said.

Of course, the U.S. decision to drawdown its presence at RAF Mildenhall is disappointing. However, we recognize that such changes are sometimes necessary. Michael Fallon, British Defence Secretary

While the Air Force would reduce its footprint in the United Kingdom, it announced England would be the first European country to host American F-35 Joint Strike Fighters. The British are buying their own F-35s, which will fly from the Royal Navy’s new HMS Queen Elizabeth and HMS Prince of Wales aircraft carriers.

The Air Force will base two squadrons of F-35s, each with 24 aircraft, at RAF Lakenheath in Eastern England. The base is also home to F-15 Eagles, F-15E Strike Eagles and HH-60G Pave Hawk combat search-and-rescue helicopters. F-35s are scheduled to start arriving there in 2020.

British Defence Secretary Michael Fallon called the Pentagon’s decision to base F-35s in England a “resounding vote of confidence by the U.S.”

“I am delighted that the Royal Air Force, Royal Navy and U.S. Air Force will be operating this superb aircraft alongside one another from bases in the U.K.,” he said in a statement. “It is an indication of the strength of our continuing shared commitment to transatlantic security.”

The British secretary was not so upbeat on the U.S. departure from Mildenhall.“Of course, the U.S. decision to drawdown its presence at RAF Mildenhall is disappointing,” Fallon said. “However, we recognize that such changes are sometimes necessary.”

The base consolidation will not alter the number of U.S. troops in Europe, which will stay near the current level of about 67,000, Chollet said.

Pentagon officials have been working on the European base consolidation plan for about two years. When Russia invaded Ukraine in early 2014, DOD officials considered pausing the consolidation effort, but decided to press on.

“We weren't talking about reducing our ability to conduct the mission; we were talking about our ability to do that same mission for less money, and that was an effort worth continuing,” said John Conger, who is acting assistant secretary of defense for energy installations and environment at the Pentagon.

For several years the Pentagon has said it wants to close or realign bases across the United States, a plan that has been flat out rejected by Congress.But with fewer bases, fewer U.S. and local host country support and maintenance people will be needed, Conger said.

“Approximately 1,200 U.S. military and civilian support positions will be eliminated and about 6,000 more U.S. personnel will be relocated within Europe,” he said. “Up to 1,100 host-nation positions could also be eliminated and approximately 1,500 additional Europeans working for the U.S. could end up being impacted over the next several years, as many of their positions are relocated to areas we need to maintain for the long term.”

Some of those reductions will be offset by 1,200 new positions associated with the two new F-35 squadrons at Lakenheath.

A full list of the bases being consolidated or closed is here.