The Brazilian embassy has been surrounded by troops and police
The UN Security Council has called on the interim government of Honduras to "cease harassing" the Brazilian embassy housing deposed leader Manuel Zelaya.
The council also condemned "acts of intimidation" against the embassy and appealed for services including water and electricity to be restored.
The call came after Brazil's foreign minister said he was worried that Mr Zelaya might be "forcefully arrested".
Mr Zelaya took refuge in the embassy after returning to Honduras on Monday.
He slipped back into the country almost three months after being driven out at gunpoint in his pyjamas.
The Brazilian embassy building in the capital, Tegucigalpa, has been surrounded by police and troops since Mr Zelaya appeared there.
Interim Honduran leader Roberto Micheletti has said he would arrest Mr Zelaya if he left the embassy but has pledged not to enter the compound to arrest him, the Associated Press news agency reported.
The crisis in Honduras flared when Mr Zelaya tried to hold a non-binding public consultation in July, asking people whether they supported moves to change the constitution.
His opponents said the move was unconstitutional and was aimed at removing the current one-term limit on serving as president, so paving the way for Mr Zelaya's possible re-election. He has denied this.
The Security Council issued its statement after a closed-door meeting on Friday.
The US ambassador to the UN, Susan Rice, said the embassy - not the political crisis itself - was the focus of the meeting.
Brazilian Foreign Minister Celso Amorim told the meeting that the Brazilian embassy had been "virtually under siege", and that services had been cut and food supplies disrupted.
"The Brazilian government is gravely concerned that the same people who perpetrated the coup d'etat in Honduras might threaten the inviolability of the embassy in order to forcefully arrest President Zelaya," he said.
Ms Rice said members of the council had "called upon the de facto government of Honduras to cease harassing the Brazilian embassy and to provide all necessary utilities and services, including water, electricity, food and continuity of communications".
Earlier, Mr Zelaya told the BBC's Brazilian service that he and his supporters had been surviving on a diet of biscuits until eating their first proper meal on Thursday.
The Associated Press reported that among those allowed into the embassy were human rights workers who were entering daily to deliver food, water and medicine to Mr Zelaya, his supporters and journalists.
Meanwhile, the British Foreign Office updated its travel advice for Honduras, warning against "all but essential travel" to the country for as long as the crisis continued.