Tunisian opposition parties are seeking to achieve a vote of no-confidence within the National Constituent Assembly, following the recent clashes between protesters and police in the southwestern town of Siliana.
Opposition parties will present a formal note of objection to pave the way for this step, and to express their rejection of the coalition's failure to fulfill the basic demands of the nation and handle the recent protests that have erupted in response.
Anti-government members of the assembly had walked out of a session last Friday, protesting the absence of Prime Minister Hamadi Al-Jebali from the discussion about Siliana's political unrest.
MP Mohamed Al-Baroudi pointed out that the no-confidence bid seeks to impose pressure on the government to respond to the popular demonstrations which express anger about Tunisia's growing political and economic problems.
The Islamic Ennahda Movement won the country's first free elections in October 2011 following Tunisia's revolution, which set off last year's "Arab Spring" uprisings.
The movement heads a government that also includes two secular parties, the Congress for the Republic and the Ettakatol. The coalition holds a comfortable majority of 139 seats in the 217-member body.
The Constituent Assembly elected Moncef Marzouki as president in December 2011 to follow Zine Al-Abidine, who was ousted as president in January 2011 after weeks of protests.
In a remote town in Tunisia's interior, protesters angry about joblessness and harsh police tactics having been calling for the downfall of the new Islamist rulers, echoing the revolt that ignited the Arab Spring two years ago.
Siliana, 140 kilometres (90 miles) from the coastal capital, has been convulsed, as thousands of largely unemployed youth battle riot police who fire tear gas and birdshot.
"I lost my eye because of the police; this is what Ennahda has done," says Anis Omrani, 24.
"We don't have jobs and we're marginalised, but they attack us savagely ... The police of Ennahda just add another problem," Omrani says, with a patch over one eye.
Of at least 252 wounded, medical sources say 17 have been blinded through police use of birdshot, and UN Human Rights Commissioner Navi Pillay condemned the government Friday for what she called excessive violence.
Such bloody clashes recalled Sidi Bouzid, the deprived town to the south where a street peddler burned himself to death two years ago in despair at the confiscation of his fruit cart.
His suicide provided the spark for an uprising in Tunisia that spread to Egypt, Libya, Yemen, Syria and Bahrain.
Aware of comparisons between Siliana and Sidi Bouzid, the government temporarily removed the local governor Saturday and promised jobs to victims of the 2010 uprising. Police stopped using birdshot.
Ennahda was late to respond to the protests, after first accusing leftists who lost last year's elections of fomenting unrest by provoking Tunisians in impoverished areas into confrontations that would drive away foreign investors.
The protests began on Tuesday after a call by the leftist labour union UGTT to take to the streets to demand jobs, investment and the removal of Ennahda's Islamist governor.
The protests are the fiercest since Salafists attacked the US embassy in Tunis in September over an anti-Islam film made in California, in violence that left four people dead.