The cost to rebuild Nepal after its most devastating earthquake in eight decades on April 25 will exceed $10 billion and take years, Finance Minister Ram S. Mahat says. The estimate is equivalent to about half of Nepal's $20 billion economy, reports Bloomberg Business.

A collapsed temple in the city center after an earthquake with a 7.8 magnitude shook Nepal's capital. Source: npr.org Image credit: Omar Havana/Getty ImagesThe government is struggling to save those who may still be trapped for more than 72 hours after the 7.8 magnitude temblor struck the Himalayan nation. The death toll has already exceeded 4,300 and could climb beyond 6,000, Mahat is quoted as saying in an interview.

The government will appeal to the world for help when the immediate rescue effort ends Mahat says, adding that a precise reconstruction figure is difficult to determine. “The cost is incalculable."

About a third of Nepal's 28 million people have been affected by the quake, with about 1.4 million in need of food assistance in Asia's second-poorest country.

“Due to the mountainous geography, infrastructure damage, collapsed bridges and damaged roads, access to many of the affected areas is reported to be extremely limited," the United Nations says.

Kathmandu and the valley area around it account for a third of the nation's economic activity, according to an estimate by Nepal's central bank. Other major drivers include agriculture, remittances and tourism, which may suffer after at least 18 people died in a quake-induced avalanche at the Mount Everest base camp.