The Trump administration on Tuesday formally cleared the sale of 66 new F-16 jet fighters to Taiwan in a bid to bolster the island nation's air power.

Randall Schriver, assistant defense secretary for Indo-Pacific security affairs, said the jet sale is partly a response to the growing threat posed by China.

"We've tracked the growing threat for a long time," Schriver told the Washington Free Beacon, noting annual Pentagon reports.

"In addition, part of Taiwan's air force is aging and in need of replacements," he said. "This sale is needed in order for Taiwan to keep a viable air defense,"

Secretary of State Mike Pompeo said Monday: "The president approved the notice that went up to Capitol Hill … last week so that we could move forward with these F-16 sales."

"These are deeply consistent with the arrangements, the historical relationship between the United States and China, the three communiques that layer on top of that," he told Fox News. "Our actions are consistent with past U.S. policy. We are simply following through on the commitments we’ve made to all of the parties."

The State Department made the formal congressional notification on Wednesday and said the F-16 C/D Block 70 jets, also known as the F-16V, will promote peace and stability across the Taiwan Strait and in the region.

In Taiwan, President Tsai Ing-wen said the new aircraft will bolster the country's air power.

"The deal means the nation's brand new air force is about to take off," Tsai said on social media.

Anticipating opposition to the deal from Beijing, a State Department official said the jets do not represent a shift in U.S. policy of viewing a single China under current policy and is consistent with the 1979 Taiwan Relations Act.

Along with new engines, machine guns, avionics, communications and electronic warfare gear, the estimated value of the sale is $8 billion.

New fuses and electronic components for Joint Direct Attack Munitions (JDAM) and laser-guided JDAMs were included.

On Tuesday, Trump was asked by a reporter if a recent Australian think tank report warning that China could defeat the United States in a conflict keeps him up at night.

"Well, nothing keeps me up at night," Trump said. "I'll tell you, we could wipe out anything. We have the strongest military in the world right now, and we're getting very close to finishing that whole rebuilding."

Asked if he is concerned about China's growing military power, the president said: "No, because they'd pay a price that they wouldn't want to pay."

The announcement was expected after an informal notification of the sale was sent to Congress last week.

The deal supports Taiwan's effort to modernize its armed forces in the face of growing air and missile threats from China, which has deployed more than 1,000 missiles opposite Taiwan across the 100-mile-wide Taiwan Strait.

The weapons "will contribute to [Taiwan's] capability to provide for the defense of its airspace, regional security, and interoperability with the United States," the State Department's Defense Security Cooperation Agency said in announcing the sale.

The F-16V is the newest variant of the multi-role jet fighter capable of flying at 1,500 miles per hour. It is equipped with an advanced Active Electronically Scanned Array radar, a key warfighting technology.

The fourth-generation aircraft is less capable than the more advanced F-35 stealth fighter.

The jets must contend with China's growing air force that includes newer frontline J-20 and J-35 fighters—aircraft developed with stolen American military technology.

Taiwan currently operates the F-16A/B models and thus Taipei will have no problem absorbing the new jets into its forces.

The latest deal includes engines and equipment that will be used to upgrade Taiwan's entire force of 144 F-16 A/B models.

The statement also said the jet will not alter the military balance with China, already shifted heavily in Beijing's favor.

The main defense contractor for the jets will be Bethesda-based Lockheed Martin.

The announcement made no mention of Taiwan or China and stated that the sale is a response to a request from the Taipei Economic and Cultural Representative Office in the United States, known as TECRO, the official diplomatic name for Taiwan.

Formal diplomatic relations with Taiwan were broken off in 1979 when diplomatic ties with mainland China were formalized.

Congress in 1979 stepped in with legislation to defend the long-time U.S. ally by passing the Taiwan Relations Act. Under the act, the United States is committed to providing defensive weaponry to Taiwan and to preventing China from forcibly taking over the island.

China regards Taiwan as a breakaway province and has not renounced the future use of military force retake the island.

The announced jet sale is the second major arms purchase by Taiwan.

Last month, the administration approved $2.2 billion in tanks and missiles, including 108 M1A2 tanks and 250 Stinger anti-aircraft missiles.

The jet deal was first disclosed in April by the Free Beacon.

It is the first major warplane sale since 150 F-16s were approved for export in 1992.

An administration official said the jet sale was put off for several weeks based on funding shortfalls in the Taiwanese government.

Beijing criticized the announcement and threatened to impose sanctions on the U.S. defense contractors involved in the sale.

"The U.S. arms sales to Taiwan severely violate the one-China principle and the three China-U.S. Joint Communiqués especially the August 17 Communiqué," said Foreign Ministry spokesman Geng Shuang.

"They constitute severe interference in China's internal affairs and undermine China's sovereignty and security interests," he said during a briefing.

"China firmly opposes that and has lodged serious representations and protests to the U.S. side. China will take every necessary measure to safeguard its interests, including sanctioning American companies involved in the arms sales."

U.S. defense companies are barred from selling weapons to China under sanctions imposed after the 1989 massacre of unarmed protesters in Beijing's Tiananmen Square.

Word of the deal prompted voices of support from Capitol Hill.

Sen. Jim Risch (R., Idaho), chairman of the Senate Foreign Relations Committee, praised the sale.

"These fighters are critical to improving Taiwan’s ability to defend its sovereign airspace, which is under increasing pressure from the People’s Republic of China," Risch said in a statement.

Sen. Jim Inhofe (R., Okla.) and chairman of the Senate Armed Services Committee, joined Sen. John Cornyn (R., Texas) in supporting the deal. The lawmakers said Taiwan "remains an important pillar of security and stability."

The jets will help Taiwan to "deter aggression given Beijing’s increasing assertiveness and military buildup," they said in a joint statement.

"I commend the administration for moving forward with the sale of F-16 fighter jets to Taiwan," said Sen. Marco Rubio (R., Fla.)

"As the Chinese government and Communist Party seeks to extend its authoritarian reach in the region, it is critical that the United States continue to enhance our strategic relationship with our democratic partner Taiwan through regular and consistent support," he said.

"This move is an important step in support of Taiwan’s self-defense efforts."