A U.S. Air Force F-35A Lightning II conducts a training flight with F-16 Fighting Falcons over the city of Gunsan, South Korea. Photo by Josh Rosales/U.S. Air Force/via Reuters

U.S. Defense Secretary Jim Mattis said on Friday that the U.S. is considering handing over trainer aircraft and other equipment to Vietnam to reinforce military ties between the two countries.

He also told his Vietnamese counterpart, Defense Minister Ngo Xuan Lich, that the U.S. wants to sign documents to lay the ground for further cooperation.

The People’s Army newspaper quoted the minister as saying relevant authorities of each nation should be assigned to work on building this cooperation.

At their meeting on the sidelines of the Shangri-La dialogue, a security forum in Singapore, the two leaders agreed that that cooperation between Vietnam and the U.S. has contributed to maintaining peace and stability in the region and the world, the report said.

The military relationship between Vietnam and the U.S. has developed strongly in recent years, with the two countries putting the Vietnam War enmity behind them.

In a May 25 meeting, Defense Secretary Mattis and Vietnamese ambassador to the U.S. Pham Quang Vinh discussed ways to boost bilateral co-operation on maritime security amidst growing tensions in the South China Sea, known as the East Sea in Vietnam.

In late March, U.S. delivered six patrol boats to Vietnam's Coast Guard. The boats are part of a $20 million hardware and infrastructure package agreed upon by both countries.

Earlier that month, U.S. aircraft carrier the USS Carl Vinson’s historic visit to the central city of Da Nang marked a monumental milestone in the diplomatic relationship between the two countries. The event garnered global attention, being the first time a U.S. Navy aircraft carrier has docked in the country, four decades after the end of the Vietnam War.

Other markers of the strengthening defense relations between Vietnam and the U.S. are former President Obama’s 2016 decision to lift the ban on the sale of assault weapons to Vietnam, and the current administration’s identification of Vietnam as a “cooperative maritime partner.”

For the first time, the U.S. has invited Vietnam to join the 2018 Rim of the Pacific (RIMPAC) Exercise, one of the world’s largest multinational naval drills held every two years, according to American military newspaper Stars and Stripes.

The international maritime exercise slated for June 27- August 2 is expected to mobilize 26 nations, 47 surface ships, five submarines, 18 national land forces, and more than 200 aircraft and 25,000 naval forces.