The United States has transferred six patrol boats to the Vietnam coast guard, to help build security cooperation between the two countries, U.S. embassy in Hanoi said in a statement on Tuesday.

U.S. President Donald Trump has expressed his hope for a stronger relationship with Vietnam, after the Obama administration put ties on a stronger footing amid Vietnam’s territorial dispute with China in the South China Sea.

The patrol boats, which were included a defense cooperation memorandum agreed in 2011, will help Vietnam in intercoastal patrols and law enforcement, the statement said.

It also added that delivering these vessels deepens cooperation in the areas maritime law enforcement, search and rescue, and humanitarian assistance operations within Vietnam’s territorial waters and exclusive economic zone.

“Vietnam’s future prosperity depends upon a stable and peaceful maritime environment. The United States and the rest of the international community also benefit from regional stability,” U.S. Ambassador Ted Osius said.

Vietnam is the country most openly at odds with China over the waterway since the Philippines President Rodrigo Duterte took a softer line with Beijing.

China claims 90 percent of the potentially energy-rich South China Sea. Brunei, Malaysia, the Philippines, Vietnam and Taiwan lay claim to parts of the sea, through which about $5 trillion of trade passes each year.