A Kenyan and a Nepali climber have died close to Everest's summit, tourism officials said Thursday, taking this season's toll on the world's highest mountain to at least four.

Joshua Cheruiyot Kirui, 40, and his Nepali guide Nawang Sherpa, 44, went out of contact Wednesday morning and a search team was deployed on the 8,849-metre (29,032-foot) high mountain.

"The team have found the Kenyan climber dead between the summit and the Hillary Step, but his guide is still missing," Khim Lal Gautam, chief of the tourism department's field office at the base camp, told AFP.

Another Nepali climber, Binod Babu Bastakoti, 37, died at about 8,200 metres (26,902 feet) on Wednesday, a statement from the tourism department said.

Search parties are also still looking for a 40-year-old British climber and his Nepali guide who went missing Tuesday morning after a snow mass collapsed as they descended from Everest's peak.

A Romanian climber died in his tent on Monday during a bid to scale Lhotse, the fourth-highest mountain in the world.

Everest and Lhotse share the same route until diverting at around 7,200 metres.

Two Mongolian climbers went missing this month after reaching Everest's summit and were later found dead.

Two more climbers, one French and one Nepali, have died this season on Makalu, the world's fifth-highest peak.

Nepal has issued more than 900 permits for its mountains this year, including 419 for Everest, earning more than $5 million in royalties. 

More than 500 climbers and their guides have already reached the summit of Everest after a rope-fixing team reached the peak last month.

China also reopened the Tibetan route to foreigners this year for the first time since closing it in 2020 because of the Covid-19 pandemic.

Nepal is home to eight of the world's 10 highest peaks and welcomes hundreds of adventurers each spring, when temperatures are warm and winds typically calm.

More than 600 climbers made it to the summit of Everest last year but it was also the deadliest season on the mountain, with 18 fatalities.