Vietnamese president Tran Dai Quang has died aged 61.
The official Vietnam News Agency said Mr Quang died at the 108 Military Hospital in Hanoi on Friday due to a serious illness.
Quang hosted US president Donald Trump during his first state visit to the communist country last year.
His last public appearance was at a Politburo meeting of the ruling Communist Party and a reception for a Chinese delegation on Wednesday.
Mr Quang did not appear in public for more than a month last year, raising speculation about his health.
A career security officer, Mr Quang was elected president in April 2016.