Talks between Tunisian political leaders on choosing a new prime minister have been suspended indefinitely late on Monday Al Arabiya reported.
"We have decided to suspend the national dialogue until there are favorable grounds for talks to succeed," said Houcine Abassi, head of the UGTT union federation mediating the crisis, in statements carried by Agence France-Presse.
"We didn't reach a consensus on the person who will lead the government. We tried to resolve the differences but there was not consensus," he added.
The halt came after participants failed to agree on a premier to drive the country out of crisis.
Talks began between the ruling Islamists and opposition leaders on October 25 to form a government of independents.
The opposition demanded the current government's resignation for failing to control jihadists.
Under the plan, a new premier was to have been named on Saturday, a week after the talks began, but when that failed a new deadline was set for Monday noon.
As the latest meeting got under way the moderate ruling Islamist Ennahda party and the opposition warned failure to reach a consensus by the end of the day would spell the demise of the so-called national dialogue launched last month.
The two frontrunners for premier are opposition-backed 79-year-old Mohamed Ennaceur, and Ahmed Mestiri, an 88-year-old supported by Ennahda and its allies.
Both are well respected and served under the late Habib Bourguiba, who led the fight for Tunisia's independence and served as its first president for three decades from 1957.
The opposition says Mestiri is too old and would be a puppet in the hands of Ennahda, which in turn insists he can strike a balance between the rival sides.
"We don't see any alternative to Ahmed Mestiri," Ennahda chief Rached Ghannouchi said after the failed talks.
The ruling coalition "made the dialogue fail. They are looking for any means to stay in power," countered Hamma Hammami, a representative of the opposition National Salvation Front coalition.