A summit of African leaders from war-torn Sudan's neighbours Thursday urged an end to the fighting, as UN experts reported a mass grave had been discovered in the country's Darfur region.

The International Criminal Court (ICC) meanwhile said it has opened a new probe into alleged war crimes in Sudan, adding that the escalating violence was a "matter of great concern".

While Cairo hosted the crisis meeting on the nearly three-month-old conflict, gun battles, explosions and the roar of fighter jets again shook the Sudanese capital Khartoum, residents told AFP.

As much of the world swelters in record temperatures, spare a thought for Issam Genedi, who ekes out a living washing cars in one of the planet's hottest regions, the Gulf.

Pausing from his work at an outdoor carpark in Dubai, the Egyptian migrant says the United Arab Emirates' furnace-like summer feels even hotter this year.

"This summer is a little more difficult than other years," says Genedi, who shines cars for about 25 dirhams ($6.80) a time in temperatures that pass 40 degrees Celsius (104 degrees Fahrenheit) each day.

Mohammed Hamid Nour is only 23, but he is already nostalgic for how Iraq's Mesopotamian marshes once were before drought dried them up, decimating his herd of water buffaloes.

Even at their centre in Chibayish, only a few expanses of the ancient waterways -- home to a Marsh Arab culture that goes back millennia -- survive, linked by channels that snake through the reeds.

Pull back further and the water gives way to a parched landscape of bald and cracked earth.

From subtly shifting the position of Ramses II's sceptre, to touch-ups on a necklace or headdress, ancient Egyptian artists were more creative than previously thought, according to a study published Wednesday.

Using new portable imaging and chemical analysis techniques, an international team of scientists took a fresh look at paintings in the Valley of the Kings -- a royal burial ground for pharaohs and other ancient Egyptian elites.

The United Nations on Wednesday said nearly three months of war in Sudan have uprooted more than three million people, and called for the warring sides to face "accountability".

Britain said it was taking action. It announced sanctions on businesses it said were associated with Sudanese military groups on both sides of the conflict.

Fighting has raged in the northeast African country since mid-April, when army chief Abdel Fattah al-Burhan and his former deputy Mohamed Hamdan Daglo, who commands the paramilitary Rapid Support Forces (RSF), turned on each other.

Israeli fire wounded three members of Lebanon's Iran-backed Hezbollah movement on Wednesday near the border with Israel, a security source in southern Lebanon said.

The incident comes amid tensions along the Israel-Lebanon border area, a stronghold of the Shiite movement and the site of sporadic skirmishes.

"Three Hezbollah members were wounded by Israeli fire near the border," the source told AFP, requesting anonymity as they were not authorised to speak to the media.

Cyprus said Wednesday that for the first time in years the number of migrants it is repatriating has outpaced those seeking asylum on the eastern Mediterranean island.

The EU member state argues it is a "frontline" country in terms of migrant arrivals, with asylum-seekers now making up five percent of its population of 915,000, a record for the bloc.

Cyprus has over the past year accelerated efforts to repatriate illegal residents and rejected asylum seekers to multiple countries within and outside the European Union.

Syrians in the country's last rebel enclave expressed alarm Wednesday after the United Nations Security Council failed to renew an aid delivery mechanism to the area, imperilling critical humanitarian assistance.

The UN largely delivers relief to northwest Syria via neighbouring Turkey through the Bab al-Hawa crossing, but the deal to do so expired on Monday.

Russia on Tuesday vetoed a nine-month extension of the agreement, and then failed to muster enough votes to adopt just a six-month extension, during a vote at UN headquarters in New York.

Iran's supreme leader Ayatollah Ali Khamenei accused Western countries Wednesday of endangering the lives of Ukrainians so they can sell arms to Kyiv for use in its war against Russia.

Western nations have pushed "the people of Ukraine to the frontlines in order to fill the pockets of American arms-manufacturing companies", Khamenei said during a meeting with senior clerics and seminary students in Tehran.

The UN Human Rights Council voted Wednesday to condemn recent Koran burning incidents, but many countries declined to back the resolution, fearing it encroached on free speech.

Despite overwhelming condemnation of the Muslim holy book being desecrated, the vote brought more division than unity, with countries from Europe and the Americas saying a bit more work could have resulted in a stronger, unanimous decision.