Spain's prime minister had earlier called for Honduras' interim leaders to restore democracy to the country.
"We won't accept the coup," Jose Luis Rodriguez Zapatero told world leaders gathered at the United Nations General Assembly meeting in New York.
The United Nations has suspended electoral assistance worth about $1.3m to Honduras, saying that conditions in the country are "not favourable" for polls scheduled for November.
Ban Ki-moon, the UN secretary general, announced the move on Wednesday, but added that it would be temporary.
UN technical aid to the country's electoral court began in September 2008 and included the training of polling station staff as well as gender and public information training.
Thousands of Zelaya supporters have held demonstrations outside the Brazilian embassy since the deposed president returned home.
At least one person has been reported killed and several wounded in the series of clashes between Zelaya's supporters and security forces.
More than 100 people have been detained.
There appeared to be some diploamtic progress on Wednesday as the military-backed government said it would receive an Organisation of American States (OAS) delegation tasked with establishing dialogue between the de facto government and Zelaya.
The OAS mission was invited by the de facto foreign minister, the US state department said on Wednesday.
Brazil and Venezuela have led calls at the United Nations General Assembly in New York for Zelaya, who was ousted three months ago, to be reinstated immediately.
On Tuesday, the de facto Honduran government said it was willing to talk to Zelaya if he recognised the legality of November's presidential elections.
|Manuel Zelaya continues to reside inside the Brazilian embassy [AFP]
Roberto Micheletti, the man who replaced Zelaya, had repeatedly threatened to arrest Zelaya if he tried to return to Honduras.
He had also previously said he would not reopen negotiations with Zelaya and insisted that Brazil should hand over the ousted leader to "pay for the crimes he committed" which he said included corruption and violating the constitution.
But on Tuesday the interim leader said he would "talk with anybody anywhere at any time, including with former President Manuel Zelaya".
Oscar Arias, the Costa Rican president who unsuccessfully mediated in talks between Zelaya and the interim government in July, told Al Jazeera that he was working on hosting a new round of negotiations.
"I think it is much more civilised if we re-start the negotiations ... so I have invited both the foreign minister of the de facto government and the Zelaya people to re-initiate this dialogue in my country," he said.
Soldiers backed by the supreme court and congress toppled Zelaya at gunpoint and sent him into exile in his pyjamas in a coup on June 28 following his attempt to call a constitutional referendum on presidential term limits.