More than 40 teams of mountaineers kicking their heels on the lower slopes of the Himalayas in Nepal heaved a sigh of relief Friday as the way to Mt Everest was opened following China's successful attempt to take the Olympic torch to the top.

'We anticipate improved weather conditions from May 16,' said Ang Tshering Sherpa, chief of Nepal Mountaineering Association, the body entrusted with promoting mountaineering in Nepal.

'Statistics show that traditionally, the period May 21-27 is the best time to attempt Mt Everest and succeed.'

A total of 41 expeditions have been shuttling from the base camp of Mt Everest to the third camp, located at an altitude of 7,374 m, to acclimatise themselves to the freezing cold and rarefied air, where breathing becomes an ordeal due to lack of oxygen.

While 29 expeditions are headed for Mt Everest, the remaining 12 are seeking to climb Mt Lhotse.

They had been ordered by Nepal's ministry of culture, tourism and civil aviation not to proceed beyond the third camp in order to prevent any anti-China demonstrations by Tibet activists that could have marred the progress of the Olympics torch.

In view of the protest rallies in some parts of the world during the torch relay, China has not given any expedition permission to attempt the peak from Tibet.

The unprecedented ban would remain in force till August, when the Olympic Games are held in Beijing.

Bowing to China's request to ban Everest expeditions, its smaller neighbour Nepal had halted Everest aspirants till May 10.

However, with the Chinese Olympic torch team accomplishing the feat Thursday morning, the curb has been withdrawn.

Meanwhile, in Kathmandu, Nepal and China patted each other on the back for pulling off the Olympic torch's conquest of Mt Everest.

Nepal Prime Minister Girija Prasad Koirala sent a congratulatory message to Chinese President Hu Jintao, calling the Olympic Games the symbol of peace, understanding and solidarity and a great opportunity to spread the message of world peace.

China reciprocated by sending its envoy to Nepal, Zheng Xianglin, to meet Koirala to formally thank him for the 'cooperation' shown by Nepal to take the torch to the world's roof.

Nepal came under intense criticism from mountaineers for the unprecedented ban as well as censorship imposed in the Everest region.

Climbers were not allowed to carry any electronic equipment, including satellite phones and cameras, and any messages sent down had to be vetted first by government officials.

On the eve of the torch's arrival at the summit, Nepal also expelled an American climber and deported him after security searches found a 'Free Tibet' banner in his backpack.