By Patrick Markey and Tarek Amara
TUNIS (Reuters) - Tens of thousands of Tunisians took to the streets on Saturday to renew their demands that the Islamist-led government step down and end a political deadlock threatening the North African country's fledgling democracy.
It was the largest protest since Tunisia's crisis erupted over the killing of an opposition leader in July, increasing pressure on the ruling Ennahda party to make way for a caretaker government before proposed elections.
Waving red and white national flags and pictures of slain opposition leader Mohamed Brahmi, protesters packed streets around a building where a national assembly had been drafting a new constitution until its work was suspended due to unrest.
"It's over for them, they should leave," said sports teacher Houssem Ben Hassen at the rally, wrapped in a Tunisian flag. "We need a government for all Tunisians."
Divisions between Tunisia's Islamists and their secular opponents have widened since the uprising that ousted President Zine al-Abidine Ben Ali, a revolt that triggered unrest across the Arab world and toppled rulers in Egypt, Libya and Yemen.
Tunisia's transition since that revolt has been relatively peaceful, with the moderate Islamist Ennahda party sharing power with smaller secular parties.
But tensions have increased in the nation of 11 million since Brahmi was killed in July, just months after another secular opposition figure was murdered by gunmen who authorities say were tied to radical Islamists.
Drawn-out wrangling over political control, elections and a new constitution now threatens transition and economic growth in a country once seen as the most promising example for the region's nascent democracies following the "Arab Spring".
The head of the constituent assembly about to finish drafting the new constitution halted its work after the July opposition leader's assassination, throwing the country's transition plan for a caretaker cabinet and elections off track.
Facing a vote analysts say it may lose, Ennahda has said it is willing to step down, but asked for at least a month to allow the national assembly to finish writing the constitution and to negotiate over the composition of the caretaker government.
After talks failed to end the standoff this week, Tunisia's opposition Salvation Front - a mix of leftists and traditional parties including leaders who once served under Ben Ali - threatened to intensify protests against Ennahda.
"We have to put more pressure on the government so they step down. There is no other solution," said Jilani Hammami, an opposition member. "If we wait for Ennahda, then they will carry on for two months and keep on with their programme."
While the Egyptian army's overthrow of Islamist President Mohamed Mursi in July following mass protests against him has further emboldened the anti-Islamist opposition in Tunisia, it is unlikely to follow Egypt's path.
With its strong links to Europe and a non-political military staying out of the fray, most analysts see Tunisia weathering its current crisis to hold elections despite disagreements over how and when the poll will happen.
"The contours of a compromise have been sketched: a new technocratic government and the approval of the constitution within the space of a month or two," said Riccardo Fabiani, a Middle East analyst with London-based Eurasia Group.
"The real obstacle is the issue of when the current government should leave and a new one should be formed."
(Editing by Sonya Hepinstall)