A construction project undertaken as part of the country's "toilet revolution" is being investigated after the roofs and walls of the structure were left unfinished - leaving embarrassed villagers to use the "open toilets".

More than 50 restrooms were planned in Fenghuang village, Loufan county in Shanxi province, in 2016, but a misunderstanding over who was responsible for funding left the project incomplete.

The county's Patriotic Health Campaign Committee Office said the finance department is channeling money into the work and the project will resume soon, China National Radio reported on Sunday.

According to the county's bureau of health and family planning, funding was provided by county and city-level finance departments, which gave 1,000 yuan separately for each of the restrooms to be built, while the villagers were supposed to come up with the money for the restrooms' roofs and walls.

However, the bureau said, the villagers mistakenly believed that the government would be responsible for all the costs.

Liu Yuexi, the village's Party chief, said the project was suspended for lack of investment back in 2016. The restrooms remain unfinished because the villagers couldn't afford the rest of the construction costs.

"Building a restroom with modern sanitary standards costs each household 3,000 yuan ($460) on average, with the roof and walls accounting for more than one-third of the total, which is a lot of money for a family in our village," Liu said.

The so-called toilet revolution, launched in 2015 by the former China National Tourism Administration, is a national campaign aiming to improve sanitary conditions at tourist attractions and in rural areas.