Israel's Benjamin Netanyahu has lashed out at a newly agreed coalition which looks set to remove him from power after 12 years as prime minister.
Mr Netanyahu called on right-wing members of parliament to block the coalition from taking office.
Eight opposition parties reached an agreement to work together to form a new government late on Wednesday.
But the group, from across Israel's political spectrum, still needs parliamentary backing to take office.
In his first comments since the coalition was announced, Mr Netanyahu urged members of the Knesset (parliament) "elected by votes from the right" to oppose the coalition.
In a post on Twitter, he criticised them as "left-wing" and "dangerous".
He has previously called the proposed new government the "fraud of the century", saying it endangered the state and people of Israel.
Observers have already noted that Mr Netanyahu - who failed to form his own coalition despite his Likud party winning the most seats in the March vote - is likely to try to prevent the group getting the support it needs.
The coalition, formed by Yair Lapid, leader of the centrist Yesh Atid party, needs the parliamentary vote before being sworn in. It is unclear how long this will take, and there is still a chance this newly formed alliance could be upended by defections.
Mr Lapid, whose party came second in the election, called President Reuven Rivlin to let him know the agreement had been reached on Wednesday night.
He pledged to form a government which would "work in the service of all Israeli citizens... respect its opponents and do everything in its power to unite and connect all parts of Israeli society".
However, Mr Lapid will not become prime minister immediately. Under a rotation arrangement, the head of the right-wing Yamina party, Naftali Bennett, would serve as prime minister first before handing over to Mr Lapid in August 2023.
The coalition members span the full spectrum of Israeli politics with little in common apart from their plan to replace Mr Netanyahu.
For the first time in decades, the government will include an Israeli Arab party.
An image carried on Israeli media showed Mr Lapid, Mr Bennett and Mansour Abbas, leader of the Arab Islamist Raam party, signing the agreement, a deal many thought impossible.
If the coalition fails to win the support of a majority in the 120-seat Knesset, there is a risk of a fifth election in two years.
All eight parties were needed to secure the 61-seat majority.
Reaction to the agreement has been mixed. According to news agency AFP, other parties representing Israeli Arabs - who make up 20% of the population - have said they will oppose a government led by Mr Bennett, who rejects the concept of a Palestinian state.
Meanwhile, right-wing politicians have also voiced concerns. "The left is celebrating but it is a very sad day for the State of Israel," Miki Zohar, a prominent Likud member wrote on Twitter, saying the right-wing parties in the coalition "should be ashamed".
But elsewhere there was jubilation. Protesters who had been demanding Mr Netanyahu's resignation danced in the street.
Some were just relieved at the prospect of an end to the political turmoil which has seen Israel hold four elections in just two years as politicians struggled to find someone to unite behind.
"I think that the political situation has been deadlocked for too long," protester Zvi Yosef told Reuters news agency. "We have to try something new, even though it's a little bit scary and there's a lot of unknowns. But at the moment, I don't see any other option."
Source: BBC