A permanent ceasefire could risk more violence in Israel and Palestine at the moment, Sir Keir Starmer is expected to say.
The Labour leader will make a speech on Tuesday calling on global leaders to work towards restoring peace in the Middle East amid the ongoing Israel-Hamas conflict.
But Sir Keir will defend Labour’s calls for a humanitarian pause to allow Palestinians to flee the fighting, and for aid to be distributed.
He is expected to say that a permanent ceasefire at this stage could leave Hamas with the capability to carry out further attacks in Israel.
Humanitarian pauses typically last for short periods of time with the aim of providing aid and support rather than achieving long-term political solutions, according to the United Nations.
Ceasefires are intended to be long-term and usually seek to allow parties to engage in talks, including the possibility of reaching a permanent political settlement.
The Labour leader’s latest intervention on the conflict comes as several MPs on his frontbenches have broken ranks to call for a ceasefire, contradicting his support for a humanitarian pause.
Shortly before Sir Keir’s speech, Alex Cunningham became the latest shadow minister to call for an immediate cessation of violence, describing it as “heartbreaking” to see “ordinary people caught up in horrors”.
“There must be an immediate ceasefire to get vital aid to Palestinians, give the UN a chance seek the release of Hamas-held hostages and end the deadly attacks on Palestinian and Israeli people,” he said.
Yasmin Qureshi, Jess Phillips, and Imran Hussain are among other figures who have joined calls for an end to the fighting.
Labour has also been at odds over its stance on Israel with devolved mayors like Andy Burnham and Sadiq Khan, and with Labour-led councils across England.
But the party is not likely to sack its internal critics from frontbench roles, and will instead “continue engaging” with them, shadow science secretary Peter Kyle said on Sunday.
Middlesbrough MP Andy McDonald has meanwhile been suspended by Labour, after what a party spokesman said were “deeply offensive” remarks made at a speech during a pro-Palestine rally.
Mr McDonald said his reference to the phrase “between the river and the sea” was part of a “heartfelt plea” for peace in the region.
A slogan used by pro-Palestinian demonstrators, “from the river to the sea, Palestine will be free”, has been described as antisemitic by critics, with Home Secretary Suella Braverman claiming that it is “widely understood” to call for the destruction of Israel.
Mr McDonald, now sitting as an independent, said he would fully co-operate with the investigation into his suspension and trusted “that the whip will be restored”.
