Aid-dependent Nepal needs $7.86bn over five years, $1.17bn more than earlier estimates, to rebuild homes and infrastructure destroyed by the deadly earthquake in 2015, the government said on Thursday.

In total, 9,000 people were killed across Nepal in the 7.8 magnitude quake, which the government said had affected 2.8mn of the Himalayan nation's 28mn population.

International donors, who pledged $4.1bn for reconstruction last year, have been left frustrated as little of that fund has been spent because of haggling between political parties, leading to a delay in helping millions of survivors.

Authorities said the increase in the amount of aid required was due to a larger scale of destruction than initially projected.

The Red Cross says 4mn people are still living in poor-quality temporary shelters, posing a threat to their health.

"The increased requirement of funds is due to a rise in the number of people affected," Prime Minister K.P. Oli told lawmakers in Kathmandu.

"The government will construct community houses and move survivors who are living in the open to roofed shelters," Oli said.

Reconstruction of private homes will be completed in two years, he added, urging donors to provide additional support for rebuilding.