The Ukraine war has shown the heavy toll military conflict takes not just on people but also on the planet, say experts at the UN climate summit in Egypt.

From the emissions caused by diesel-powered tanks, fighter jets and missile blasts to urban and forest fires and massive waves of refugees, the conflict has also spewed out huge amounts of greenhouse gases.

"This is a field of significant emissions and nobody has really dealt with this problem," said Axel Michaelowa, head of the University of Zurich's International Climate Policy research group.

Qatar has agreed to allow special direct flights from Israel that will be open to both Israeli and Palestinian fans for the World Cup, FIFA announced on Thursday.

But the accord gave few details on how decades of hostility would be overcome so that Palestinians and Israelis can travel on the same charter jets to the first World Cup in an Arab nation.

"Today's historic announcement provides a platform to improve relations across the Middle East," said Gianni Infantino, president of FIFA, world football's governing body.

Qatar on Thursday opened a huge expansion of its main international airport as the national carrier's chief hit back at "rumours" that it could not cope with World Cup passengers.

After the multi-billion dollar overhaul, Hamad International Airport will take its capacity from 40 million passengers a year to 58 million, Qatar Airways chief executive Akbar Al Baker told a news conference.

The expansion adds 39 airport gates to the existing 140 at the airport, which is a major hub for transit passengers.

Russia's war in Ukraine has forced a short-term scramble for fossil fuels but the rise of solar, wind and other clean energies is "unstoppable", the head of International Renewable Energy Agency told AFP.

Speaking at the UN COP27 climate summit in Egypt, Francesco La Camera said market forces now all but ensure renewables will keep growing fast -- but also warned that the pace will need to double to prevent a climate catastrophe.

A sister of Egypt's jailed dissident Alaa Abdel Fattah quickly disputed a claim by the prosecutor Thursday that the hunger striker was in "good health," as fear mounts that he is being force-fed.

Relatives have repeatedly demanded information on the health of the British-Egyptian activist in recent days, after he escalated his months-long hunger strike and stopped even drinking water as the COP27 climate summit opened in the North African nation on Sunday.

Fossil fuel lobbyists have flooded UN climate talks in Egypt, a report by watchdog groups said Thursday, even as calls grow at the summit for a windfall tax on oil majors' bumper profits.

More than 600 lobbyists from some of the world's biggest polluters have registered to the climate talks in the Egyptian resort of Sharm el-Sheikh, up 25 percent from last year, the analysis by groups including Global Witness and Corporate Accountability found.

That is more than the number of representatives from the 10 most climate-affected countries combined, they said.

US President Joe Biden returns to the world stage with a spring in his step after midterm elections he sees proving that, in the global contest between democracy and autocracy, good guys don't always come last.

Biden is scheduled to leave Washington on Thursday for the COP27 climate summit in Egypt the next day, an ASEAN regional summit in Cambodia at the weekend and the gathering of G20 major economic powers in Indonesia next week.

The tense midterms campaign had left the world wondering which Biden would show up.

Religious and far-right politicians, who have compared gay people to animals and demanded an end to Pride rallies, are poised to enter the next Israeli government sparking fear among the LGBTQ community.

After veteran leader Benjamin Netanyahu topped the polls earlier this month, he is expected to form a coalition with two ultra-Orthodox Jewish parties and the extreme-right Religious Zionism alliance.

One far-right lawmaker, Avi Maoz, set the tone last week, telling army radio: "We're going to study the legal avenues to cancel Gay Pride."

US climate envoy John Kerry urged Pacific island states on Thursday to join global efforts to cut methane emissions in hopes it would sway major emitters China and India to follow suit.

Speaking at the UN's COP27 summit in Egypt, Kerry said 20 countries have yet to count methane as part of their pledges to cut emissions in global efforts to limit warming to 1.5 degrees Celsius.

"In those 20 states are China and India, and that's a massive amount of methane," he said at the event on protecting the oceans.

An Iranian general claimed Thursday that the Islamic republic had developed a hypersonic missile capable of penetrating all defence systems, raising concerns from the UN nuclear watchdog.

Hypersonic missiles, which like traditional ballistic missiles can deliver nuclear weapons, can fly at more than five times the speed of sound.

"This hypersonic ballistic missile was developed to counter air defence shields," General Amirali Hajizadeh, the commander of the Islamic Revolutionary Guard Corps aerospace unit, was quoted as saying by Fars news agency.