Nepal appeals for more helicopters for its quake relief operations, as survivors complain they are getting little help from only 20 in operation. Photo: BBC

Nepal says 6,204 people are known to have died in the 7.8-magnitude quake and 13,932 were injured.

But the fate of thousands more in many remote areas remains unknown.

The government has warned that the death toll could rise to more than 10,000.

One thousand EU citizens remain unaccounted for in the quake that hit during the height of the trekking season, the EU ambassador to Nepal, Rensje Teerink, told reporters.

Relief and rescue teams have reached most areas but many people remain in urgent need.

At the scene - Sanjoy Majumder, BBC News, Kathmandu

At Kathmandu's historic Durbar Square, soldiers and volunteers form human chains to remove the debris, brick by brick.

The bricks come from temples and other historic buildings levelled by the earthquake. Many are very old and are being stored so that they can be used to rebuild these ancient sites.

The soldiers are joined by aid workers - but also tourists. One French visitor said she "just wanted to help". But it's an ad hoc approach which characterises the entire relief operation.

I met rescue and medical teams from France and China. After wandering around they left. "We don't know what we are supposed to be doing," one French rescue worker told me.

Their services are required in the remote villages where many are in urgent need of assistance - but they are stuck here in the capital because no-one is telling them what to do.

Landslides and poor weather have hampered efforts to reach isolated districts.

"Almost every house in my village is destroyed, and 20 people died," Kumar Ghorasainee told the AFP news agency amid the ruins of his hometown of Melamchi in Sindhupalchok, north-east of Kathmandu.

The region has been identified by the Red Cross as one of the worst-affected areas.

"We lost our cattle and our sheep," the 33-year-old English teacher said. "No-one has come to help us - the cars and the aid trucks just drive by... How will we manage now?"

There are only about 20 helicopters available for the rescue and relief operations taking place in a region that stretches hundreds of kilometres.

Near the quake epicentre, the Red Cross speaks of "almost total devastation"

"Inaccessibility to some remote areas, the lack of helicopters, poor communication and security concerns remain the main challenges in delivering relief," said Farhan Haq, a United Nations spokesman.

The UN on Wednesday launched a "flash appeal" for $415m (£270m) to assist Nepal over the next three months - but on Friday it told the BBC it had so far received only $5.8m - 1.4% - in confirmed funding.

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There has been growing anger at the government's response to the disaster, with a number of protests breaking out.

In the capital Kathmandu, shortages of food and water have forced thousands of workers to board buses and flee to their home towns and villages.

A lack of buses and the slow distribution of aid have led to clashes between protesters and riot police.

The tent cities which sprang up around Kathmandu in the days following the quake have almost gone, reports say, as the fear of aftershocks subsides.

But the stench of rotting bodies in the rubble has driven officials to order that unclaimed bodies be cremated immediately after they are recovered, Reuters news agency reported.

The UN has also warned of the challenges facing Nepal's farming community, which comprises up to two-thirds of the country's 27 million people.

It says that the quake destroyed seed stocks for the mid-May rice sowing season, as well as grains kept dry in stone storage huts that have now been razed to the ground.

If farmers miss this month's planting season, they will be unable to harvest rice - Nepal's staple food - until late 2016, the UN says.