World leaders take centre stage at UN climate talks in Dubai on Friday, under pressure to step up efforts to limit global warming as the Israel-Hamas conflict casts a shadow over the summit.

The COP28 conference kicked off on Thursday with an early victory as nations agreed to launch a "loss and damage" fund for vulnerable countries devastated by natural disasters.

But delegates face two weeks of tough negotiations on an array of issues that have long bedevilled climate talks, starting with the future of fossil fuels.

The sense of urgency was heightened by a UN warning that 2023 is on track to become the hottest year on record, raising fears the world will not meet the goal of limiting warming to 1.5 degrees Celsius.

"Now the real work only begins," the oil-rich UAE's COP28 president Sultan Al Jaber said on Thursday.

"I will be rolling up my sleeves myself, engaging and helping address this challenge and delivering real, actionable results," Jaber said, though he claimed there was "positivity" and an "optimistic" vibe following the loss and damage announcement.

Jaber, who heads the UAE's national oil firm ADNOC, said the "role of fossil fuels" must be included at the UN's climate talks.

Activists, countries hardest hit by climate impacts and UN chief Antonio Guterres have called for a phase out of fossil fuels, which are responsible for three quarters of greenhouse gas emissions.


Gaza war 
The spotlight now turns to more than 140 kings, presidents and prime ministers who will address delegates at the sprawling Expo City Dubai complex on Friday and Saturday.

Britain's King Charles III will kick off those addresses, followed by leaders from nations including the likes of Brazil, Kenya, Tonga and Ukraine.

But the climate crisis will share the agenda with the conflict in Gaza.

Israeli President Isaac Herzog met UAE counterpart Sheikh Mohammed bin Zayed Al Nahyan on Thursday and will be among the leaders addressing the COP28 conference on Friday.

Palestinian counterpart Mahmud Abbas had also been scheduled to speak but his office told AFP that he was no longer going and his foreign minister would go to Dubai instead.

The conference began on Thursday with a moment of silence -- at the request of the Egyptian head of last year's COP -- for the civilians who have died in the conflict.

The war began on October 7 when Hamas and other militants from Gaza poured over the border into Israel, killing around 1,200 people, mostly civilians, and kidnapping about 240, according to Israeli authorities.

Aiming to destroy Hamas, Israel retaliated with an air and ground offensive that the Hamas government in Gaza says has killed more than 15,000 people, also mostly civilians, and reduced large parts of the north of the territory to rubble.

Herzog is using his COP28 visit for a diplomatic push to secure the release of hostages held by Hamas.

He "appealed" to his Emirati counterpart "to employ his full political weight to promote and speed up the return home of the hostages," the Israeli president's office said in a statement.

US Vice President Kamala Harris, who will represent the United States at COP28, will meet with regional officials on the Israel-Hamas conflict, according to the White House.

Secretary of State Antony Blinken on Thursday said that a temporary truce in the conflict was "producing results" and should continue.

As part of the week-long pause in fighting, Hamas has freed dozens of hostages taken during last month's attack on Israel in exchange for the release of more than 200 Palestinian prisoners being held in Israeli jails.