Activists from Tunisia's ruling Islamist party Ennahda gathered in central Tunis Saturday to protest the right of their movement to lead the government, amid ongoing talks to form a new cabinet of technocrats.

Dozens of protesters, many of them sporting beards and waving party flags and banners, demonstrated on Habib Bourguiba Avenue, cradle of the 2011 uprising that ousted president Zine El Abidine Ben Ali, shouting: "Supporting Ennahda is a duty."

They also jeered ex-premier Beji Caid Essebsi and the secular opposition party Call of Tunisia which he heads, and which portrays itself as an alternative to the ruling Islamists.

The gathering comes ahead of a planned mass rally later on Saturday called by Ennahda to denounce Prime Minister Hamadi Jebali's plan to form a government of technocrats in a bid to resolve Tunisia's worst political crisis since the revolution.

Jebali, who is number two in the ruling Islamist party, first announced his plan to form a non-partisan government last week, in the wake of public outrage over the killing of leftist leader Chokri Belaid, laying bare divisions within the party.

The prime minister has said he would resign if he fails to get the support he needs.

After he met the leaders of the main political parties on Friday, he said talks on the new administration had been rescheduled for Monday and that a previous Saturday deadline its formation had been cancelled, with no new date set.

Ennahda was repressed under Ben Ali's regime but emerged as a powerful political force after his overthrow in January 2011, with its veteran leader Rached Ghannouchi returning from 20 years in exile to a hero's welcome.

It won the first post-revolution polls in October 2011, taking 41 percent of the seats in the National Constituent Assembly, and securing the key foreign, interior and justice ministries in the coalition government.

Ennahda hardliners are refusing to give up key portfolios, insisting on the party's electoral legitimacy.

The family of Belaid, who was a scathing critic of the ruling Islamists, has accused Ennahda of orchestrating his murder, a claim the party strongly denies.

Belaid's supporters are planning two memorial ceremonies on Saturday.

Tensions between liberals and Islamists have been simmering for months over the future direction of the once proudly secular Muslim nation.

A controversial group linked to Ennahda and implicated in attacks on secular opposition groups said on Saturday that its president, Mohamed Maalej, was resigning in order to form a political party.

Created in May 2012, the League for the Protection of the Revolution has been accused by civil society and opposition groups of carrying out brutal attacks that shocked Tunisians and have prompted calls for its dissolution.