Israeli Prime Minister Benjamin Netanyahu and his rival Benny Gantz traded blame Sunday over the failure so far of efforts to reach a unity government deal following deadlocked elections.
A new round of negotiations between Netanyahu's right-wing Likud and Gantz's centrist Blue and White broke down Sunday and the two sides appeared far from reaching a compromise.
Likud said Netanyahu would make a "last effort" to reach a deal before informing President Reuven Rivlin he is unable to form a government.
That would leave Rivlin to decide whether to ask Gantz to try to do so or call on parliament to agree on a candidate for prime minister by a vote of at least 61 out of 120 members.
Netanyahu "will make a last effort to realize the possibility of forming a government at this stage, before returning the mandate to the president," Likud said in a statement, according to AFP.
It called the latest round of negotiations a "big disappointment."
Blue and White accused Likud of "throwing around slogans with the sole aim of generating support in preparation for dragging Israel into another round of elections at the behest of Netanyahu."
This month's poll was the second this year, after Netanyahu failed to form a coalition following April polls.
Israel marks the two-day Rosh Hashanah holiday beginning Sunday night and serious negotiations are not expected during that time.
Likud wants to negotiate on the basis of a compromise set out by Rivlin to form a unity government, which takes into account the possibility of Netanyahu being indicted for corruption in the weeks ahead.
The proposal could see Netanyahu remain prime minister for now, but step aside if indicted.
Gantz would step in as acting premier under such a scenario.
Netanyahu also says he will not abandon the smaller right-wing and religious parties supporting him in parliament, giving him a total of 55 seats backing him for prime minister.
Blue and White says Gantz must be prime minister first under any rotation arrangement, since it finished with the most seats in September 17 elections.
Blue and White won 33 seats, just ahead of Likud's 32, but neither have a clear path to a majority coalition.
Gantz has 54 parliament members backing him for prime minister, but 10 are from Arab parties who say they will not serve in the ex-military chief's government.
Rivlin tasked Netanyahu with trying to form a government Wednesday and he has 28 days to do so, with a two-week extension possible.
The deadlocked vote has threatened Netanyahu's reign as Israel's longest-serving prime minister.
If another election is called due to the standoff, it would be Israel's third in a year.