Nepal protests at Everest video call by climber Hughes
Nepal's tourism ministry has demanded to know why a British climber made a video call from the summit of Mount Everest without permission.
Daniel Hughes reached the top of the world's highest peak on 19 May, and spoke live to BBC News from there using his smartphone.
Nepalese officials have summoned his expedition leader, David Hamilton, to be questioned by a committee.
An official said Mr Hughes had broken the rules on broadcasting.
Dipendra Poudel from the mountain section of Nepal's Ministry of Culture, Tourism and Aviation told the BBC: "The mountaineering rules say if you want to make a live telecast from the mountain, which is a restricted area, you have to get a permit first and inform us early about what you're going to do.
"It costs around $2,000 (£1,324) to get this permit."
Ministry officials said mountaineers found guilty of violating Nepal's tourism laws could be banned from obtaining climbing permits for 10 years or banned from entering the country for five years.
Mr Hughes, who has now left Nepal, aimed to raise £1m ($1.6m) for the British charity Comic Relief by climbing Mount Everest and carrying out what he said would be the world's first video call from the summit.
During the call the climber wore an oxygen mask as well as a red nose, which is the Comic Relief symbol.
The expedition leader told the BBC that he was trying to reach an amicable settlement with the ministry. Mr Hamilton said he had been operating in Nepal for the past 20 years without infringing local laws and sensibilities.
"If we realised this filming was going to be an issue, we would have tried to head it off at the beginning.
"As far as we see it, the rules are a little bit grey about shooting short video clips and putting them on websites."
The BBC's former Nepal correspondent, Joanna Jolly, says the incident demonstrates that the country's broadcasting regulations have not kept up with technological progress.
May is the most popular month for climbing Everest due to favourable weather, and the past weeks have seen several firsts on the world's highest mountain.
They include a record 11th ascent by a British mountaineer, the first by a Saudi woman and the ascent of the oldest person yet to conquer the peak, 80-year-old Yuichiro Miura, from Japan.