The ruling Ennahda party will leave power and negotiations will begin to set up a caretaker government before new elections can be scheduled, Euronews reported Saturday.
The protests began after two prominent leaders of the opposition movement were killed, including Chokri Belaid, the BBC said. An estimated 1 million people attended his funeral.
The Ennahda party, a moderate Islamist group, blamed hard-liners for Belaid's death but many in the opposition have charged Ennahda has turned a blind eye and failed to reign in the more radical Islamist elements.
Tunisia has been in political turmoil since 2011, when activists forced the ouster of former dictator Zine al-Abidine Ben Ali in a movement that spread to other Arab nations and sparked what would come to be known as the Arab Spring.