FILE - A Lockheed Martin F-35 aircraft is seen at the ILA Air Show in Berlin, Germany, April 25, 2018.    REUTERS/Axel Schmidt/File Photo - RC1FC93131E0
FILE - A Lockheed Martin F-35 aircraft is seen at the ILA Air Show in Berlin, Germany, April 25, 2018.

Updated July 17, 2019, 10:27 p.m.

PENTAGON — The United States is officially removing Turkey from its F-35 stealth fighter jet program after Ankara accepted the Russian delivery of its S-400 missile defense system.

“Unfortunately, Turkey’s decision to purchase Russian S-400 air defense systems renders its continued involvement with the F-35 impossible,” the White House said in a statement Wednesday. “The F-35 cannot coexist with a Russian intelligence collection platform that will be used to learn about its advanced capabilities.”

U.S. officials believe NATO ally Turkey’s decision to use Russian advanced radar technology could compromise the alliance’s military systems in the country. The S-400 could potentially be used to target NATO jets in Turkey, including the U.S.-made F-35, which is NATO’s newest stealth fighter jet.

WATCH: US Removes Turkey from F-35 Jet Program

Under Secretary of Defense for Acquisition and Sustainment Ellen Lord told reporters at the Pentagon Wednesday the U.S. and its other F-35 partners “were aligned” in the decision to suspend and begin formally removing Turkey from the program.

“Much of the F-35’s strength lies in its stealth capabilities, so the ability (of the S-400) to detect those capabilities would jeopardize the long-term security of the F-35 program,” she said.

$9 billion in projected work

Turkish companies had made more than 900 parts for the F-35 and is set to lose more than $9 billion in projected work over the life of the program, including $1 billion in current commitments, Lord said. She added the U.S. was spending between $500 million and $600 million to shift the supply chain out of Turkey.

All Turkish pilots and aircraft maintenance people training with the F-35 program have plans to leave the United States by July 31, according to the Pentagon. Turkey’s involvement in the program will officially “wind down” by the end of March 2020, Lord said.

In a statement issued late Wednesday, Turkey’s foreign ministry called the decision to exclude it from the F-35 program a mistake, dismissing the Pentagon’s concerns.

The statement also warned the U.S. decision would cause irreparable harm to relations between Washington and Ankara.

Turkey’s NATO involvement

Despite such protests, key Western officials tried to minimize the damage while continuing to express disappointment over Ankara’s decision to accept delivery of Russia’s S-400.

“I am concerned about the consequences of the Turkish decision,” NATO Secretary General Jens Stoltenberg told a security forum in Aspen, Colorado, late Wednesday. “It’s bad for all of us.”

“But Turkish contributions to NATO and NATO’s cooperation with a NATO ally, Turkey, runs much deeper than the F-35,” Stoltenberg added, highlighting Turkey’s contributions in the fight against the Islamic State terror group and to NATO missions in the Balkans.

The NATO chief did not rule out Turkey’s future contributions to NATO’s integrated air and missile defense system and rejected talk of kicking Turkey out of the alliance.

Defense Secretary nominee Mark Esper testifies before a Senate Armed Services Committee hearing on his nomination in Washington, July 16, 2019.

In Washington, Deputy Under Secretary of Defense for Policy David Trachtenberg said the U.S. would continue to participate with Turkey in international exercises in Georgia, Germany and Ukraine, but it remains unclear how or whether Turkey would be allowed to participate in any NATO or U.S. exercise involving air defense.

“The United States greatly values our strategic relationship with Turkey. That remains unchanged,” Trachtenberg said.

On Tuesday, President Donald Trump’s nominee to be the next secretary of defense slammed Turkey’s acceptance of the S-400, parts of which were delivered last week, as “wrong” and “disappointing.”

Mark Esper told lawmakers he emphasized in a phone call to Turkey’s Defense Minister Hulusi Akar that “you can either have the S-400 or the F-35. You can’t have both.”

Military vehicles and equipment, parts of the S-400 air defense systems, are unloaded from a Russian transport aircraft, at Murted military airport in Ankara, Turkey, July 12, 2019.

A Russian transport jet delivered the first parts of the $2.2 billion missile system last Friday to a Turkish military air base outside Ankara.

Turkey’s Ministry of National Defense has said its purchase of the S-400 defense systems was “not an option but rather a necessity.”

The ministry said last week that Turkey was still assessing the bid to acquire U.S. Patriot air defense systems.

But the White House countered Turkey’s assertion Wednesday.

“The United States has been actively working with Turkey to provide air defense solutions to meet its legitimate air defense needs, and this administration has made multiple offers to move Turkey to the front of the line to receive the U.S. PATRIOT air defense system,” the White House said.

The White House added that Turkey has been a “long-standing and trusted partner and NATO Ally for over 65 years,” but that “accepting the S-400 undermines the commitments all NATO Allies made to each other to move away from Russian systems.”