Tunisia's opposition alliance on Monday called for country-wide protests next week, accusing ruling Islamists of holding up the start of negotiations and delaying the formation of a new government.
Political activity has ground to a halt in Tunisia since the murder of opposition MP Mohamed Brahmi in July, amid a bitter standoff between the ruling Islamist party Ennahda and the opposition.
The National Salvation Front (NSF), a loose coalition of opposition parties, called on Tunisians "in all regions, especially the capital" to take part in a "massive demonstration on October 23 to demand the appointment of a competent government."
The date marks the second anniversary of the election of the National Constitution Assembly, which was tasked with promulgating a new constitution but has failed to do so amid deep mistrust among political factions.
The opposition coalition on Monday accused Ennahda of manoeuvering to buy time and of aggravating Tunisia's political crisis by not sticking to its commitment to negotiate the formation of a cabinet of independents.
Ennahda agreed on October 5 to respect a roadmap aimed at creating a new government within three weeks and ending the political deadlock plaguing the country since Brahmi was shot dead on July 25.
Under the blueprint, a new constitution and electoral law must be adopted and a timetable drawn up for fresh parliamentary and presidential polls.
But the Islamists have since questioned the timing of the new government's formation, saying any countdown can only be agreed upon once a national dialogue on unresolved political issues has begun.
A date for those negotiations has yet to be fixed, with the parties so far only holding preparatory meetings, and with the NSF insisting that they begin no later than October 19.
As Tunisia's political crisis drags on, the country is also grappling with an armed jihadist movement, which is blamed for Brahmi's murder and which the opposition says Ennahda has failed to rein in.
The ruling Islamists are also accused of mismanaging the economy and failing to improve living standards.
Poor social conditions were seen as a driving factor behind the 2011 revolution that toppled longtime ruler Zine El Abidine Ben Ali and sparked the Arab Spring.