HANOI, Vietnam (AP) — The Philippines and Vietnam signed an agreement Tuesday on preventing and managing incidents in the disputed South China Sea during Philippine President Ferdinand Marcos, Jr.'s visit to Hanoi.

Several countries, including the Philippines and Vietnam, are locked in maritime disputes with China over its claims of sovereignty over virtually the entire South China Sea, one of the world’s most crucial waterways for shipping, and high-seas faceoffs between Chinese and Philippine ships have intensified over the past year in the contested waters, fueling fears of a wider conflict.

The Philippines and Vietnam agreed Tuesday to increase coordination on maritime issues and work to promote trust and confidence, the Philippine government said in a statement.

They didn’t release details about what actions they would take under the agreement.

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“Vietnam remains the sole strategic partner of the Philippines in the ASEAN region,” Marcos said during a meeting with his Vietnamese counterpart, Vo Van Thuong, referring to the regional grouping of Southeast Asian nations.

He added that while maritime cooperation was the “foundation” for this partnership, relations between the two nations had expanded.

The two countries also signed a deal on Tuesday for Vietnam to supply the Philippines with 1.5 million to 2 million metric tons (1.6 to 2.2 million U.S. tons) of rice each year at affordable prices.

Vietnamese rice accounts for 85% of imported rice in the Philippines and the two countries agreed to create a framework for ensuring stable supplies. A rice shortage last year, exacerbated by climate change and some major producers halting exports, resulted in prices soaring globally including in the Philippines.

Marcos, who arrived in Hanoi on Monday, also met with Pham Nhat Vuong, Vietnam’s richest man and the chairman of the sprawling conglomerate Vingroup, which runs the electric vehicle company Vinfast.

Vinfast said after the meeting it would open an EV business network in the Philippines and that the investment would start later this year.

VinFast’s plans to expand in the Philippines are part of its goal of selling EVs in 50 markets worldwide. It is exporting EVs to the U.S. and also building a $4 billion EV factory in North Carolina, where production is slated to begin this year. It has also said it will build factories in Indonesia and India.