A remote region of Nepal is hoping to improve local sanitation by asking everyone who applies for a citizenship card or passport whether they have a toilet at home, an official said Thursday.

Authorities in the rural midwestern district of Surkhet say only one in three households there has a toilet, below the national average of 45 percent, while the district headquarters has only one public toilet for 44,000 people.

They say there is a lack of awareness of the health risks related to open defecation, and are hoping the proposed scheme will help to eradicate the practice.

"We decided we have to motivate and put pressure on people to build toilets in their houses," regional sanitation engineer for Surkhet, Prem Krishna Shrestha, told AFP.

"Of course, we cannot deny them their right to citizenship. The idea of the programme is to make sure that people understand the value of having a toilet in their houses.

"So when someone comes to get a passport or citizenship card, the officials will ask if they have a toilet in their house."

The proposal comes as Nepal is struggling to deal with a diarrhoea outbreak that has reportedly killed around 150 people in a remote western region.

Disease outbreaks are common during the monsoon, when floods mean water sources can easily become contaminated.

The government has promised to eradicate open defecation by 2017, but Shrestha said it was well behind schedule on the building of new toilets.

"Nepal should be building 320,000 toilets a year and records show only around 100,000 to 125,000 toilets are being built. We have a lot of catching up to do," he said.