Israeli President Isaac Herzog is due to attend the UN climate talks in the United Arab Emirates Thursday where he will hold talks with diplomats on the release of hostages held by Hamas.
His visit comes seven weeks into the Israel-Hamas war and coincides with a day-long extension of truce that had been due to expire on Thursday, amid ongoing attempts to release more hostages.
At COP28, which will also be attended by Palestinian president Mahmud Abbas, Herzog will hold a "series of diplomatic meetings on the importance of releasing the hostages held by Hamas", the Israeli presidency said in a statement.
He "intends to engage world leaders in a high-level humanitarian effort to return the hostages", the statement said.
More than 140 heads of state and government are due to address COP28 on Friday and Saturday, including Herzog and Abbas who are both scheduled to make speeches lasting three minutes on Friday.
Since the truce began on November 24, 70 Israeli hostages have been freed in return for 210 Palestinian prisoners.
Around 30 foreigners, most of them Thais living in Israel, have been freed outside the terms of the deal.
Israel has made clear it sees the truce as a temporary halt intended to free hostages, but there are growing calls for a more sustained pause in the conflict.
Fighting began on October 7 when Hamas and other militants from the Gaza Strip poured over the border into Israel, killing 1,200 people, mostly civilians, and kidnapping about 240, according to Israeli authorities.
In response, Israel vowed to destroy Hamas and unleashed an air and ground military campaign that the Hamas government in Gaza says has killed nearly 15,000 people, also mostly civilians, and reduced large parts of the north of the territory to rubble.
The war has cast a shadow over the UN climate talks in Dubai with activists planning actions to express solidarity with Gaza.
On Thursday, climate activists will hold a press conference to demand a permanent ceasefire in Gaza and an end to Israel's 17-year blockade of the enclave.
"The climate movement see the struggle of the Palestinian people against occupation and apartheid as part and parcel of our collective struggle for climate" justice, said a statement by the COP28 Coalition, a global network of climate justice and human rights organisations.