MAJUWA, Nepal — With help still not reaching some isolated villages a week after Nepal’s devastating earthquake, a top international aid official said Saturday that more helicopters were needed to get assistance to the farthest reaches of this Himalayan nation.

Many mountain roads, often treacherous at the best of times, remain blocked by landslides, making it extremely difficult for supply trucks to get to the higher Himalayan foothills.

“We definitely need more helicopters,” Ertharin Cousin, executive director of the U.N.’s World Food Program, told The Associated Press in the village of Majuwa, in the quake-devastated Gorkha district. Aid agencies have been using Majuwa as a staging area to get supplies to mountainous areas. “Even seven days in this is still very much considered the early days, because there are people we still haven’t reached. So we need helicopters to reach them.”

Cousin said shelter was a more urgent priority at this point than food.

The magnitude-7.8 earthquake killed more than 6,840 people, with the death toll continuing to rise as reports filter in from isolated areas. The U.N. has estimated the quake affected 8.1 million people — more than a fourth of Nepal’s population of 27.8 million.