Mount Everest climbing season began this week, with new rules requiring climbers to bring down their personal rubbish, and more security officials at the mountain's base camp.

Tourism Ministry official Maddhu Sudan Burlakoti said individual climbers going beyond the base camp will be required to bring down at least eight kilograms of their personal rubbish.

It is the latest attempt by the Nepalese government to clean up the world's highest mountain, which draws hundreds of Western climbers and a steady income for the local and national economy, but produces a lot of waste.

Until now, climbing teams were asked to bring down their rubbish or risk losing a 4,000 US dollar deposit - a rule which was not widely enforced.

More than 4,000 climbers have scaled the 8,850-metre summit since it was conquered in 1953 by Edmund Hillary and his Sherpa guide Tenzing Norgay. Over the years, climbers have left tons of rubbish on the slopes, and some have called it the "world's highest garbage dump".

Burlakoti said officials posted at the base camp would check climbers to make sure that each brings down food wrappings, tents, ropes, clothes, crampons, pegs and gas cans. It was not clear how climbers failing to comply would be punished.

The government is also opening up a contact office tent at the base camp with officials stationed there throughout the spring climbing season that begins in March and ends in May. They will offer help to climbers and resolve any problems between climbers and monitor the rubbish situation.

Last year, a brawl between Western climbers and their Nepalese guides on the mountain sparked safety concerns.

Nepal officials say the rules will protect the environment, better manage climbers and increase their safety, especially as their numbers grow.

Nepal has eight of the 14 highest mountains in the world.