Tunisia's Islamist-backed prime minister resigned Tuesday after failing to form a new government in response to the assassination of a leading secular opposition figure earlier this month.
Prime Minister Hamadi Jebali quit hours after saying his own Ennahda party had rejected his plan for a government of technocrats.
Jebali had announced his push for a non-partisan government February 6, just hours after secularist leader Chokri Belaid was shot to death at close range outside his home in the capital, Tunis. Belaid's supporters had accused Ennadha of being behind the killing, a charge the ruling party denies.
Hours after the killing, with mass opposition protests gripping the capital, Belaid's Popular Front party pulled out of the constituent assembly charged with writing a new constitution.
Ennadha party leader Rached Ghannouchi is expected to confer Wednesday with President Moncef Marzouki on his party's candidate for the job.
Tunisia was the epicenter of the 2011 Arab Spring protest movement that swept through North Africa and led to the ouster of Tunisian President Zine El Abdine Ben Ali and later to the downfall of Egyptian President Hosni Mubarak.
Analysts say the current deadlock has left the North African country paralyzed and vulnerable to more violence that authorities fear from hardline Islamist Salafists.