The crew — two Russians and a Belarussian — were also killed in Monday’s crash along with three Nepalese nationals, it said in a statement.
The chopper went down amid poor weather conditions.
According to Swedish military sources, Mats Norhult, a 54-year-old officer and UN observer from Värmland in western Sweden is believed to have perished in the crash.
Although the United Nations has said 10 people died in the crash, the local police and Nepal’s home ministry say they recovered 12 bodies from the scene, some 85 kilometres (50 miles) east of the capital Kathmandu.
The names of the foreigners will be released once their families have been informed, the statement said.
The head of the UN peace mission to Nepal paid tribute to the dead.
“They died while working to sustain peace in Nepal, and the United Nations Mission in Nepal will continue in the midst of this tragedy to apply its best efforts to this purpose,” said Ian Martin.
The United Nations is monitoring a peace process that ended a decade of war between the Kathmandu government and former rebel Maoists.
The chopper was returning from a visit to a camp containing former Maoist guerrillas when it went down, the UN said.