The US secretary of state met with Vietnam prime minister Pham Minh Chinh on Saturday, two weeks after the 50th anniversary of the withdrawal of American combat forces from South Vietnam that marked the end of US direct involvement in the Vietnam war.
It comes as China has reportedly refused to let Mr Blinken visit Beijing.
Chinese officials are concerned that the FBI will release the results of an investigation into a Chinese “spy balloon” downed over North American airspace, according to reports.
A new $1.2 billion US embassy campus has opened in the Vietnamese capital, in a project intended to demonstrate US commitment to improving ties.
Breaking ground at the new campus, Mr Blinken said it represented “another significant step toward strengthening a vital partnership between our countries and between our people.”
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