Thousands of people lined the streets of Hanoi on Friday to pay their final respects to Communist Party general secretary Nguyen Phu Trong, the most powerful leader Vietnam has seen in decades.

The 80-year-old, who died in hospital in the capital last week, led the party since 2011 and oversaw a high-profile anti-corruption drive that swept through the party, police, armed forces and business.

At 1:00 pm (0600 GMT) Friday, Trong's wooden coffin was carried out from Hanoi's national funeral house by guards of honour and top leaders, including President To Lam and Prime Minister Pham Minh Chinh.

Draped in Vietnam's red and yellow national flag, the coffin was placed on what appeared to be a gun carriage and driven in convoy through the capital's tree-lined streets, packed with back-clad mourners. 

Residents waved as the convoy drove past on its way to Mai Dich cemetery, the final resting place for many senior leaders in Vietnam, and said: "Long live Uncle Nguyen Phu Trong!"

Children and war veterans were among those waiting in 37-degree-Celsius (99-degree-Fahrenheit) heat holding portraits of the leader.

At the burial site, Trong's family stood as his coffin -- emblazoned with the Chinese symbol of longevity -- was lowered into the ground by 10 soldiers in crisp white uniforms. 

The burial followed a two-day funeral attended by Vietnam's top leaders, foreign officials, school children and Buddhist monks.

"Trong was an especially outstanding leader... a loyal communist party member with huge credibility," President Lam said at the funeral.

"His name, career, talent and ethics will forever be with the party, the nation and the people," added Lam, who was handed the reins of power a day before Trong's death was announced.

Flags at half mast

A four-hour slot for the public to pay their respects at the funeral house late Thursday had to be extended due to the huge number of people in line.

"I spent more than four hours queueing last night," Tran Hoang Nguyet Mai told AFP on Friday.

"Luckily I got into the funeral house to say farewell to a leader that I really respect," she said. 

"He was the last true communist that thought of no benefits for himself and his family."

Since Thursday, more than 250,000 people had paid their respects to Trong at ceremonies in Hanoi, southern Ho Chi Minh City and his village on the outskirts of the capital, authorities said Friday afternoon.

All flags across the country flew at half mast, while entertainment and sporting events have been suspended during the two-day mourning period.

Trong's poor health had fuelled widespread speculation that he would not be able to stay in power until the 2026 party congress.

He enjoyed remarkable longevity in office, during a mandate that rights groups say has coincided with increasing authoritarianism.

Trong was praised earlier by US President Joe Biden as "a champion of deep ties" between Vietnam and the United States, while Russian President Vladimir Putin hailed the Vietnamese leader as a "true friend of Russia".