The U.S. is planning to more than quadruple the number of troops in Taiwan as part of an effort to harden the island against a potential invasion by China, reported the Wall Street Journal on Thursday.

“The U.S. plans to deploy between 100 and 200 troops to the island in the coming months, up from roughly 30 there a year ago, according to U.S. officials. The larger force will expand a training program the Pentagon has taken pains not to publicize as the U.S. works to provide Taipei with the capabilities it needs to defend itself without provoking Beijing,” reported Nancy A. Youssef. “The number of American troops, which has included special-operations forces and U.S. Marines, has fluctuated by a handful during the past few years, according to Defense Department data. The planned increase would be the largest deployment of forces in decades by the U.S. on Taiwan, as the two draw closer to counter China’s growing military power.”

Ever since Communists established the People’s Republic of China, Taiwan has played host to a government-in-exile founded by the Nationalists. China’s government considers Taiwan to be inseparable from their country.

The United States has formally recognized the “One China” policy for decades as part of normalizing relations with China, but does not recognize Chinese sovereignty over Taiwan, which Chinese leaders claim to be part of the policy. The U.S. has also assisted Taiwan with its security against the possibility of the Chinese government invading and deposing its leaders by force.