Philippines' Marcos says maritime cooperation a cornerstone in Vietnam visit

"We hope to strengthen this aspect during my visit to promote peace and stability in our region," Marcos said in a statement before leaving for Hanoi for a two-day state visit.

Marcos is expected to meet Vietnam's top officials and work on agreements on coastguard cooperation and rice supply. Vietnam is a major rice exporter and the Philippines is one of the world's biggest importers of the grain.

Marcos said he hopes his visit would bring their relations to greater heights and "usher in a new era of friendship and cooperation", with talks on trade, investment, education and tourism, as well as "regional and multilateral issues of concern."

Vietnam and the Philippines have overlapping claims in the South China Sea, but have generally friendly relations compared to the heightened tensions between Manila and Beijing over disputed waters.

Ties between the Philippines and China have deteriorated this past year, coinciding with a tougher stand by Manila and overtures by Marcos to forge stronger military relations with the United States.

The South China Sea, a conduit for more than $3 trillion in annual ship-borne commerce, is claimed almost entirely by China via a U-shaped line policed by its vast coastguard fleet, which cuts into the exclusive economic zones of Vietnam, the Philippines, Malaysia, Brunei and Indonesia.

In 2016, the Permanent Court of Arbitration in the Hague said China's claims had no legal basis, a decision Beijing has rejected.