By Maayan Lubell

JERUSALEM (Reuters) -Israeli Prime Minister Benjamin Netanyahu will undergo surgery on Sunday for a hernia, his office said, at a time when he is waging a war against Hamas in Gaza, and less than a year after he was fitted with a pacemaker.

“On Saturday night, during a routine checkup for Prime Minister Benjamin Netanyahu a hernia was found,” his office said in a statement, adding that the 74-year-old leader will be under general anaesthetic during his surgery later on Sunday.

Signalling his condition was not serious, Netanyahu’s office announced he would hold a news conference at 1630 GMT, before the procedure.

“I assure you that I will get through this treatment successfully and return to action very quickly,” Netanyahu told reporters at the conference.

Netanyahu was fitted with a pacemaker last July, while Israel was ensnared in its worst domestic crisis in decades, with widespread protests against his hard-right government’s judicial overhaul plan.

Those protests stopped on Oct. 7, when the Palestinian Islamist Hamas group launched its shock attack on southern Israel, killing 1,200 people and taking more than 250 hostage back to Gaza.

It was Israel’s deadliest single day and the worst attack on Jews since the Holocaust. Israel then launched an air, sea and ground offensive in Gaza, with the declared aim of ending Hamas’ rule there and dismantling its military capabilities.

More than 32,000 Palestinians have been killed in the war and Israel has faced intense and growing international pressure over the death toll and the grave humanitarian crisis in Gaza.

Netanyahu’s popularity, already down over the judicial crisis, has plummeted further since the war, with successive opinion polls showing little faith in his leadership and a defeat by more centrist rivals if an election were held.

With around 130 hostages still in Gaza, there have been steady protests against Netanyahu’s government over its failure to get them home. The government is facing a new crisis over exemptions of ultra-Orthodox Jewish men from military service, an issue that is splitting opinion within the prime minister’s own cabinet.

Now in his sixth term, Netanyahu is Israel’s longest-serving leader. He is also the country’s first sitting premier to be indicted with corruption. His trial is still ongoing and he denies any wrongdoing.

Justice Minister Yariv Levin will be standing in for Netanyahu during the operation on Sunday, his office said.