The government's chief negotiator, Communications Minister Jorge Rodriguez, said "electoral guarantees" for the vote would be on the table -- as would the issue of US economic sanctions that have worsened Caracas' precarious finances.
"We are working on all the issues and we have narrowed positions on all the issues," he said as he arrived at the Dominican Republic's foreign ministry, the venue for the talks overseen by several Latin American foreign ministers.
The latest round of negotiations opened on December 1.
Other topics being discussed are the government's demand that the opposition recognize the Constituent Assembly -- a legislative body filled with Maduro loyalists that overrides the opposition-dominated parliament -- and solutions for the economic crisis, marked by hyperinflation and lack of food and medicine.
Friction between the government and the opposition coalition, the Democratic Unity Roundtable (MUD in Spanish), rose last week when the Constituent Assembly announced that presidential elections, due for December, were being brought forward to some time before the end of April.
The Supreme Court, which the opposition says systematically bows to Maduro, issued a ruling that excludes the MUD coalition from the election. Only individual opposition parties are allowed to register.
The opposition, struggling with internal divisions and thus far unable to rally behind a single unifying figure, says the moves are designed to deliver Maduro a second term.
Some key parties are refusing to register for the election.
One of its negotiators, lawmaker Enrique Marquez, said MUD was demanding international election observers monitor the polls.
Venezuela's government is finding itself increasingly isolated internationally over the path taken by Maduro, whom the United States has called a "dictator."
Argentina has said it will not recognize the results of the presidential election. And French President Emmanuel Macron has called for sterner European sanctions on Venezuela to pressure Maduro's regime.
US Secretary of State Rex Tillerson is to conduct a Latin America tour late this week and into next week in which Venezuela's turmoil is expected to top the agenda.