Philippine officials say they will soon begin negotiations with the United States on a larger U.S. military presence to help deter what they say is increasing Chinese aggression in Philippine-claimed waters in the South China Sea.

In a letter to Philippine congressional leaders, the secretaries of national defense and foreign affairs said that allowing U.S. troops to have an “increased rotational presence” will help the country attain a “minimum credible defense” to guard its territory while it struggles to modernize its own military, one of Asia’s weakest.

A larger American presence would also mean more resources and training for responding to disasters in a nation often battered by typhoons and earthquakes, Defense Secretary Voltaire Gazmin and Foreign Secretary Albert del Rosario said in their letter, a copy of which was obtained by the Associated Press on Thursday.

“The Philippines will shortly enter into consultations and negotiations with the United States on a possible framework agreement that would implement our agreed policy of increased rotational presence,” Gazmin and del Rosario said.

U.S. officials were not immediately available for comment.

The presence of foreign troops is a sensitive issue in the Philippines, a former U.S. colony. The Philippine Senate voted in 1991 to close down major U.S. bases near Manila.

The Philippine constitution forbids foreign troops from being permanently based in the country, but the Senate ratified a 1999 pact with the United States that allows temporary visits by U.S. forces.

Gazmin and del Rosario assured lawmakers that any new accord with Washington “will be consistent with our constitution.”

Several of China’s neighbors have been alarmed by Beijing’s recent assertiveness in claiming large areas of the South China Sea.

Manila’s desire to bolster its external defense and security has dovetailed with Washington’s intention to pivot away from years of heavy military engagement in the Middle East to Asia, where it has been fostering closer economic and military alliances with countries such as the Philippines, partly as a counterweight to China’s rising clout.

The realignment of U.S. forces in the Asia-Pacific region also involves the deployment of up to 2,500 Marines in northern Australia and the stationing of U.S. combat vessels in Singapore.

Gazmin has said that additional U.S. troops would be allowed to have access to the country’s existing military bases only under terms that the Philippines would negotiate with the U.S. government.

— Associated Press