Israeli Prime Minister Benjamin Netanyahu has said he would undergo surgery to implant a pacemaker, with lawmakers set to debate a controversial judicial reform bill that has brought hundreds of thousands of protesters to the streets.

The proposed judicial revamp proposed by Netanyahu's far-right government has split the nation and sparked one of the biggest protest movement's in Israel's history since it was unveiled in January.

The prime minister will undergo the procedure at Tel Hashomer hospital, a statement from his office said early on Sunday, with Deputy Prime Minister Yariv Levin standing in for him.

A week ago Netanyahu, 73, had been discharged from the same medical centre after a night of hospitalisation following complaints of dizziness.

"A week ago I had a monitoring device implanted and this device beeped this evening and announced that I needed to get a pacemaker. I have to do this tonight, I feel great and I listen to my doctors," Netanyahu said in a video posted on his Facebook page.

Netanyahu's latest health scare comes with lawmakers set to debate the reforms bill in parliament on Sunday to be followed by a vote on Monday.

"The doctors tell me that I will be free and I will be released from the hospital tomorrow afternoon and will be able to go to the Knesset to vote," the prime minister added.

The final vote Monday will be on the key "reasonability" clause through which judges can strike down government decisions.

Mass protests

Netanyahu's government, which includes extreme-right and ultra-Orthodox Jewish allies, plans to curb the Supreme Court's powers granted under this clause, arguing that the changes are necessary to ensure a better balance of power.

Critics accuse Netanyahu, who is on trial on corruption charges he denies, of trying to use the reforms to quash possible judgements against him. He rejects the accusation.

The "reasonability" clause was most recently cited by Israel's top court to force Netanyahu to remove a cabinet member over a previous tax evasion conviction.

If approved in the final vote Monday, it would be the first major component of the proposed legal overhaul to become law.

Other proposed reforms include giving the government a greater say in the appointment of judges.

Opponents view the proposed refo rms as a threat to Israel's democracy and since January have taken to the streets in tens of thousands.

Protests have drawn support from across political and social strata, including both the left and the right, secular and religious groups, peace activists and military reservists, as well as blue-collar and tech workers.

On Saturday, hundreds of thousands rallied in Tel Aviv, the country's commercial centre, and near parliament in West Jerusalem ahead of the final vote.

Demonstrations were also held in Beersheva, Herzliya and Kfar Saba, according to footage distributed by organisers.