Ousted Honduran leader Manuel Zelaya has said he will return to the country whether or not a deal is reached to end the political crisis.
Mr Zelaya's wife said midnight on Saturday was the deadline for a deal to be reached at talks in Costa Rica between the country's political rivals.
Earlier, Venezuelan President Hugo Chavez had said Mr Zelaya was due to return home "in the coming hours".
The interim government has vowed to arrest Mr Zelaya if he does go back.
They prevented Mr Zelaya's earlier attempted homecoming on 5 July.
Representatives of Mr Zelaya and the interim government that was appointed after he was ousted in a coup last month are preparing to meet for a fresh round of talks in Costa Rica, mediated by Costa Rican President Oscar Arias.
Mr Zelaya's wife, Xiomara Castro, said that midnight on Saturday was "the deadline" for an agreement on the country's future to be reached.
"Time runs out tomorrow," she said.
She added that the conditions were right for her husband's return and the talks "can't continue for three or four months".
"He has to come back to the country. He has to come publicly. He is not a criminal and does not need to be hiding," she said.
"All the diplomatic avenues are nearly exhausted. We hope there is a decision tomorrow."