Israel's president told lawmakers on Wednesday to name a candidate to form a new government after Prime Minister Benjamin Netanyahu and challenger Benny Grantz both failed to clinch their own coalitions.
During a 21-period mandated by law, Knesset legislators can nominate anyone in the 120-seat assembly to form a government.
If that fails, an election is triggered within 90 days, sending voters back to the polls for an unprecedented third time this year after inconclusive elections in April and September.
"These are harsh dark days in the annals of the State of Israel," President Reuven Rivlin said while announcing that centrist newcomer Benny Gantz, like four-term conservative Netanyahu before him, did not muster enough support for a stable coalition.
The two men had tied in the previous elections.
In remarks addressed to lawmakers, Rivlin said: "In the coming 21 days, there will be no 'bloc' or 'party'. Each and every person will sit with their conscience and will have to answer one question: What is my duty toward the State of Israel?"
A new and successful candidate emerging within Israel's fractious party systems looked unlikely.