But he may give in to the United States, the top trade partner of coffee-exporting Honduras, which wants Zelaya back before the November 29 vote.
The two sides sought agreement on whether the supreme court or congress would decide on the ousted leader's reinstatement, until elections are held and a new president takes office in January.
"We're going into the last phase," Vilma Morales, the spokeswoman for Micheletti's negotiators, told journalists on Friday.
But Zelaya said "the climate is extremely delicate and dangerous", although negotiators say they agree on most points of a deal based on an accord proposed by Oscar Arias, the Costa Rican president.
They include the creation of a unity government and requirements that Zelaya drop his plans to rewrite the constitution, which sparked the crisis, and that November 29 polls be held on schedule.
The latest round of talks came after months of protests and crackdowns by security forces.
Representatives of Zelaya and Micheletti finally sat down together last week to try to hammer out a settlement.
Amid a wave of international condemnation and aid freezes, the US has called for Zelaya's return to office, suspended some $30m in financial aid programmes and cancelled the US visas of senior regime officials.
Zelaya antagonised the country's elite by aligning himself with Hugo Chavez, Venezuela's president.
The political crisis has compounded economic woes in the nation of some 7.6 million people.