The coalition to oust Israeli Prime Minister Benjamin Netanyahu faces a number of hurdles including a vote of confidence in the Knesset, after it formally comes into being on Monday.
Speaker Yariv Levin is due to notify lawmakers of its official formation.
The next step for Mr Netanyahu's challengers comes at a time of heightened political tension.
On Saturday, the head of Israel's home security service issued a rare warning of possible domestic violence, raising fears that extremists could try to disrupt government formation.
Once the coalition is formally recognised by the Speaker, a confidence vote will be held on Wednesday or the following Monday, Israeli media said.
The late Friday announcement by Mr Levin, a close Netanyahu ally, allayed fears their right-wing Likud party could find procedural ways to block the formation of the coalition that would end Netanyahu's 12 consecutive years in office.
On paper, the coalition announced by opposition leader Yair Lapid, minutes before a midnight Wednesday deadline, should command a slender majority in the confidence vote.
But all eyes will be on potential defections from the disparate alliance which is united only by shared hostility to Mr Netanyahu.
Under the agreement, Naftali Bennett of the religious nationalist Yamina party would be premier for two years, to be replaced by the centrist Mr Lapid in 2023.
With possible jail time hanging over him if found guilty of corruption charges at an ongoing trial, Mr Netanyahu is not expected to give up without a fight.
This week, tensions could flare further when a Jewish right-wing march is expected to pass through the Damascus Gate in Jerusalem's Old City.
Eleven days of fighting broke out last month between Israel and Hamas in Gaza, sparked by Palestinian-Israeli confrontations in and around the Old City.
A similar march – the route of which was diverted at the last minute – was held the day the fighting broke out.
In the nearby flashpoint occupied East Jerusalem neighbourhood of Sheikh Jarrah – where the potential eviction of Palestinians by Jewish settlers played a major role in the build-up to the latest Israel-Hamas conflict – confrontations took place on Saturday.
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A Palestinian woman and an Israeli policeman scuffle during a protest against the planned evictions of Palestinian families from the Sheikh Jarrah neighborhood of East Jerusalem. AP -
Palestinians protest about local families facing eviction from the Sheikh Jarrah neighbourhood of East Jerusalem. AFP -
Palestinian families face eviction from the Sheikh Jarrah neighbourhood of East Jerusalem. AFP -
Israeli security forces detain a Palestinian during protests in the Sheikh Jarrah neighbourhood of East Jerusalem. AFP -
Fatah supporters and Archimandrite Abdullah Yulio, centre left, demonstrate in the West Bank city of Ramallah in solidarity with Palestinian families facing Israeli eviction orders in the Sheikh Jarrah neighbourhood of East Jerusalem. AFP -
Fatah supporters demonstrate in the West Bank city of Ramallah in solidarity with Palestinian families facing Israeli eviction orders in the Sheikh Jarrah neighbourhood of East Jerusalem. AFP -
Fatah supporters demonstrate in the West Bank city of Ramallah in solidarity with Palestinian families facing Israeli eviction orders in the Sheikh Jarrah neighbourhood of East Jerusalem. AFP -
Israeli mounted police move to disperse Palestinian protesters amid ongoing confrontations as Palestinian families face eviction in the Sheikh Jarrah neighbourhood of East Jerusalem. AFP
Media network Al Jazeera said one of its reporters, Givara Budeiri, was assaulted and arrested by Israeli police while covering a protest there.
Police said that Ms Budeiri had assaulted officers and had refused to identify herself.
Footage posted online showed Ms Budeiri, wearing a press vest, being pulled and pushed while led away by several officers. Al Jazeera also said the reporter's camera was smashed. She was released later.
The head of Israel's domestic security service issued a rare warning on Saturday of possible violence during one of the most politically charged periods in decades.
"We have recently identified a rise in increasingly extreme violent and inciteful discourse particularly on social networks," Nadav Argaman, head of the Shin Bet security force, said, without mentioning any names.
“This discourse may be interpreted among certain groups or individuals, as one that permits violent and illegal activity that may even cause physical harm,” he said.
Since Mr Bennett announced he was joining forces with Mr Lapid, security services have ramped up his protection, with right-wing demonstrations held near the homes of his party members, hoping to keep them from joining the government.
Mr Argaman called on political and religious leaders to show responsibility and tone down potential incitements.
His warning was reminiscent to some in Israel of the days leading up to the 1995 assassination of then-prime minister Yitzhak Rabin, who was shot by a Jewish ultranationalist for pursuing a land-for-peace deal with the Palestinians.
Mr Netanyahu's supporters have been working hard to win defections from l Yamina assembly members uncomfortable with Mr Bennett's alliance with Jewish leftists and Arab conservatives.
Demonstrations orchestrated by Mr Netanyahu's supporters have been held outside the home of Yamina Knesset member Nir Orbach, who has warned Mr Bennett he may not support him in the confidence vote.
Were Mr Orbach to vote against the deal without resigning from the party, the coalition would not have a majority.
A post on Mr Netanyahu's Facebook page said: "Those who were elected on right-wing votes have to do the right thing – to form a good, strong right-wing government."
Should last-minute defections scupper the alliance, Israel would likely have to return to the polls for its fifth election in just over two years.
