The Tunisian government was locked in talks with the main trade union confederation on Tuesday in a bid to find a compromise to avoid a rare nationwide strike, the union said.
Meanwhile President Moncef Marzouki postponed trips to Poland and Bulgaria scheduled for this week as tensions mounted ahead of the strike which the UGTT has called for Thursday, his office said.
"The talks concern the demands of the General Union of Tunisian Workers and if a compromise can be found, we could call off the strike," Ghassen Ksibi, a spokesman for the UGTT, said.
Negotiations will resume on Wednesday if talks fail to reach a compromise, he added.
The UGTT called the strike amid tensions with the ruling Islamist Ennahda party following what the union said was an attack by the party's supporters on a union demonstration in Tunis.
A union leader told AFP the UGTT demands the dissolution of the pro-Ennahda League for the Protection of the Revolution, which it accuses of carrying out last week's attack.
UGTT deputy secretary general Belgacem Ayari told the state news agency TAP that a solution to the crisis could be possible.
"There are signs of a detente, the possibility of finding a solution," he said, adding that talks on Tuesday were being held in a positive climate despite a failure at the weekend to make progress.
The December 13 general strike is to be held on the eve of the second anniversary of the revolution that ousted veteran strongman Zine El Abidine Ben Ali, amid rising social and economic tensions in the country.
Many Tunisians feel bitterly disappointed by the failure of the revolution to improve their lives, especially in the marginalised interior which suffers from a chronic lack of development and high unemployment.
Clashes, strikes and attacks, including by hardline Islamists, have multiplied across Tunisia.
The nationwide strike call is only the third to be made by the half-million strong UGTT since its foundation in the 1940s.
Observers fear that if the strike goes ahead it could spark fresh violence.
Those concerns have prompted the Tunisian president to postpone visits to Poland and Bulgaria from Thursday to Saturday, a statement from his office said, citing the "delicate situation in the country and political friction."
Marzouki will "strive to reduce the tensions," the statement added.© ANP/AFP