Vietnam will hold a funeral next week for late communist leader Nguyen Phu Trong, the party said Saturday.
Trong died on Friday at a military hospital in Hanoi "due to old age and serious illness" at the age of 80.
The funeral will take place over two days in the Vietnamese capital on July 25 and July 26, during which a period of national mourning will be observed, the Communist Party of Vietnam said.
Trong will be laid to rest at Hanoi's Mai Dich Cemetery at 3 pm (0800 GMT) on July 26, the party said in a statement.
"His death is a huge loss for the party, state and people and his family," the statement said.
Entertainment and sporting event organisers have already suspended activities, with social media users in the country changing their profile pictures to black in a show of mourning for the late leader.
Users on Facebook, X and Threads also posted photos and eulogies of the former Communist Party general secretary.
Vietnam has one of most heavily restricted media environments in the world and citizens are often hesitant to express their views online.
"A great heart has stopped," Hoang Quoc Ky wrote on his Facebook page after changing his cover photo to a picture of Vietnam's national flag flying at half-mast.
"He was a bright and perfect communist, a sharp politician... who devoted his whole life for socialism and the happiness of the people," Ky added.
"Trong was a very enthusiastic patriot in his own manner," blogger DzungArt Nguyen wrote in a Facebook post.
"(We) acknowledge his passion... may he rest in peace."
The profile pictures of social media accounts for Vietnamese state media agencies were also changed to black, with companies and NGOs in the country following suit.
In Beijing, Chinese President Xi Jinping visited the Vietnamese embassy "to mourn the passing" of his fellow communist party general secretary, state news outlet Xinhua reported.
Trong's death was announced a day after Vietnam's Communist Party said he would hand the reins of power to the country's president and former public security minister To Lam.
At the time, the party said Trong would be focusing on treatment for an undisclosed medical condition, the first time it had addressed long-standing speculation about the ageing leader's health.
The party gave no further details about Trong's illness.
Trong is the first party general secretary to die in office since the death in 1986 of Le Duan, a brother-in-arms of Ho Chi Minh.
He is also the first leader to have held three consecutive mandates at the head of the party, after the liberalisation of the economy in 1986.
