The refugees have no legal right to work or own land in Nepal
The United Nations says it has been forced to cut food aid to thousands of Bhutanese refugees living in camps in Nepal because of a funding shortage.
A senior official from the World Food Programme (WFP) warned that without adequate resources, further cuts may be necessary in the coming months.
More than 90,000 Nepali-speaking Bhutanese people have been in refugee camps in Nepal since the early 1990s.
They are dependent on food aid to meet their basic needs.
The mainly Hindu people were forced out of Bhutan, a Himalayan kingdom which has a code of national conformity.
Bhutan, which maintains that most left voluntarily, has never allowed any to return to the country.
"We are extremely concerned about the consequences of reduced rations on the health of the refugees," WFP Nepal chief Richard Ragan said in a statement.
"Without their full ration, the most vulnerable refugees will be forced to eat fewer meals or decrease portion sizes, leading to reduced nutritional status," he added.
The refugees from Bhutan live in seven camps in eastern Nepal. They fled Bhutan 18 years ago, alleging human rights abuses and discrimination.
The World Food Programme has provided rice, lentils and other foodstuffs throughout that time as the refugees have no legal right to work or own land in Nepal.
Mr Ragan said the programme needed to secure an additional $4m from donors to prevent more cuts and continue feeding the refugees into January next year.
Bhutan has refused to allow the refugees to return, but more than 20,000 have already left the camps for Western countries under a resettlement scheme.
The UN says it could take up to five years to complete this scheme and has called for urgent funding to continue feeding the refugees.