EU foreign policy chief Josep Borrell has held talks with Vietnamese President To Lam in Hanoi. They pledged to strengthen bilateral ties as the EU and Vietnam will mark 35 years of diplomatic relations in 2025.

Vietnam's state-run news agency says Lam and Borrell agreed on Tuesday to bolster trade and investment cooperation, as well as people-to-people exchanges.

The news agency also says Borrell expressed support for Vietnam's stance on the South China Sea, such as freedom of navigation and overflight, peaceful settlement of disputes, as well as adherence to international law. Hanoi has been facing Beijing's increasing assertiveness in the contested waters.

After his meeting with the Vietnamese foreign minister, Borrell stressed the EU's intention to upgrade its diplomatic relations with Hanoi to the level of a comprehensive strategic partnership.

This comes as the US and Japan have recently upgraded their diplomatic ties with Vietnam in a sign of the country's growing strategic importance.

President Lam has been active in his diplomacy. He held talks with US Secretary of State Antony Blinken on Saturday, and is scheduled to meet Hong Kong Chief Executive John Lee on Thursday.

Lam holds the second highest position in the country's political hierarchy. He is seen as the most likely candidate to succeed Nguyen Phu Trong, who had served as the country's top leader for over 10 years before dying in July.