The chief of Vietnam's ruling Communist Party Nguyen Phu Trong and U.S. President Joe Biden agreed in a telephone call on Wednesday to "promote, develop and deepen" ties, Vietnam's state media reported.
The call, a rare engagement for Biden with a foreign leader who is not a head of state or government, came as the U.S. president is hosting a second Summit for Democracy
In a statement, the White House said Biden reinforced in the call a U.S. commitment to a strong, prosperous, resilient, and independent Vietnam, adding they would work together to address regional challenges and ensure a free and open Indo-Pacific.
The United States is now Vietnam's largest export market and the two former foes are celebrating the 10th anniversary of a "comprehensive partnership" this year.
But Hanoi has been careful to ensure its ties do not alienate its giant neighbour China, while Vietnam's human rights record has been a sticking point in the relationship, with Washington critical of the government's intolerance of dissent and frequent jailing and harassment of those who speak out.
Biden also emphasized a U.S. commitment to the centrality of the Association of Southeast Asian Nations (ASEAN), respect for human rights and cooperation on climate goals, according to the White House statement.
Experts say a push by the United States to upgrade ties with Vietnam this year is facing resistance in Hanoi over concerns that China could see the move as hostile at a time of tension between the two superpowers.
"The two leaders will assign relevant authorities of the two sides to discuss details for further promoting ties," the party's official newspaper, Nhan Dan, reported.
The report said Trong, who is Vietnam's most powerful figure, and Biden repeated invitations to visit each others country. Trong had spoken with former U.S. Presidents Barack Obama and Donald Trump when they were in power.
"Vietnam consistently pursues its foreign policy of independence, self-reliance, peace, friendship, cooperation, diversification and multilateralisation of relations, active and proactive global integration," Trong said during the call, according to Nhan Dan.
In October, Trong was the first foreign leader to meet President Xi Jinping in Beijing after he secured a precedent-breaking third term as General Secretary at the Chinese Communist Party. (This story has been refiled to correct the spelling of President Xi Jinping in paragraph 11)
(Reporting by Khanh Vu in Hanoi and David Brunnstrom in Washington; Editing by Ed Davies and Michael Perry)
