Israel's Alternate Prime Minister Benny Gantz said Tuesday his party will vote for an opposition bill to dissolve parliament, a move that could force a fourth election in under two years.

Gantz's centrist Blue and White party is currently the key partner in a precarious coalition led by Prime Minister Benjamin Netanyahu's right-wing Likud.

That coalition, which was only formed after three bitterly-fought elections between Netanyahu and Gantz failed to produce a clear winner, was plagued from the outset by in-fighting and recriminations.

Gantz, a former army chief serving as defence minister, said that Netanyahu's refusal to support a budget proposal made clear that the premier wanted to take Israel back to the polls.

In a televised address he said that Blue and White "will vote tomorrow in favour of dissolving the Knesset (Israel's parliament)."

Wednesday's vote on an opposition-backed measure is however preliminary.

If it passes, it will still require multiple additional successful Knesset readings before a new election must be called.

Shortly before Gantz spoke, Netanyahu released a video on Twitter in which he urged Gantz to vote against the measure.

"Now is not the time for elections," Netanyahu said. "Now is the time for unity."

Benny Gantz, Israel's Alternate Prime Minister and Defence Minister, has announced he will vote in favour of an opposition motion to dissolve the legislature
Benny Gantz, Israel's Alternate Prime Minister and Defence Minister, has announced he will vote in favour of an opposition motion to dissolve the legislature AFP / JACK GUEZ

The Netanyahu-Gantz unity government, agreed in April, was in part aimed at providing Israel desperately-needed stability following the worst political crisis in its history and as the coronavirus pandemic was gathering pace.

Netanyahu was to serve as prime minister for the first half of the three year deal, with Gantz taking over in November 2021.

The deal included several provisions that would have automatically triggered the collapse of the coalition, including a failure to pass a budget.

Netanyahu's critics accuse of him of refusing to pass a two-year budget as a tactic to ensure he is not forced to hand over the prime minister's job to Gantz.

In a direct appeal to Netanyahu, Gantz on Tuesday urged the premier to "get cabinet to vote on a budget."

If there's a budget, "the citizens of Israel will not go to the polls in March," he said.

Some political commentators have said Gantz has decided to back the preliminary move to dissolve parliament in order to put Netanyahu in a corner and secure a public commitment from him on the budget.

Gantz also courts huge political risks by taking Israel back to the polls.

His Blue and White coalition fractured when he decided to strike a deal with Netanyahu and Gantz's personal popularity has fallen according to a series of recent polls.

His former ally turned critic, opposition leader Yair Lapid of the Yesh Atid party, is the sponsor of the dissolution bill.

"Six months after the formation of this bloated and disconnected government it is clear to everyone that Netanyahu can't lead Israel out of the corona(virus) crisis," Lapid said in a statement in which he congratulated Gantz for breaking with the coalition.