The U.S. State Department has approved a possible $100 million weapons sale to Taiwan so that the self-ruled island can improve its Patriot missile defense system amid pressure by China, the U.S government said Monday.

Taiwan expressed its appreciation for the move, with a spokesperson saying it is the second arms sale to the island under the U.S. administration of President Joe Biden.

The Biden administration has been calling on Beijing to cease its military, diplomatic and economic pressure on Taipei and has vowed to assist the island in maintaining a sufficient self-defense capability. China views Taiwan as a renegade province awaiting reunification.

The approved sale of equipment and services was in line with a request made by the Taipei Economic and Cultural Representative Office in Washington, Taiwan's de facto embassy in the United States, the U.S. Defense Security Cooperation Agency said in a press release.

"This proposed sale serves U.S. national, economic, and security interests by supporting the recipient's continuing efforts to modernize its armed forces and to maintain a credible defensive capability," the press release said.

The agency also said Taiwan is expected to use the acquired capability as "a deterrent to regional threats and to strengthen homeland defense," without directly referring to China.

If approved by Congress, the prime contractors will be Raytheon Technologies Corp. and Lockheed Martin Corp., according to the agency.