Syrian President Bashar al-Assad's British-born wife Asma, who recovered from breast cancer in 2019, has been diagnosed with leukaemia, the president's office said on Tuesday.

"First Lady Asma al-Assad has been diagnosed with acute myeloid leukaemia," an aggressive cancer of the white blood cells involved in battling infection, it said in a statement.

She will undergo a "specialised treatment protocol" that requires social distancing to avoid infection, the statement said, adding that she will "temporarily withdraw from all direct engagements as part of her treatment plan".

From camel drivers in the Sahara to nomads on the Mongolian steppe, traditional herders the world over rely on earth's wildest open spaces to support an ancient way of life.

But the expansive plains, tundra and savanna they inhabit are in much greater peril than previously thought, researchers said Tuesday in a major reassessment of the health of these crucial environments.

As much as half of all rangelands -- encompassing some of nature's most striking vistas from the Arctic to the tropics, deserts and mountains -- are believed to be degraded, the report said.

Palestinian health officials said eight Palestinians were killed Tuesday in an Israeli raid on the West Bank city of Jenin, where an AFP correspondent reported masked gunmen exchanged fire with Israeli forces.

Smoke billowed over the refugee camp adjacent to the city after a series of explosions inside, while at least five gunmen clashed with troops in a nearby downtown neighbourhood, the correspondent reported.

Human rights groups and emigre opposition factions expressed regret that Iranian president Ebrahim Raisi's death meant he never saw justice for crimes they say he committed during decades as a leading figure in the Islamic republic.

A man who rose quickly through the ranks after Iran's 1979 Islamic revolution, Raisi was accused by activists of overseeing mass executions of prisoners in 1988 followed by a litany of human rights abuses as judiciary chief and later president.

The first trial in France of officials of the Syrian regime of Bashar al-Assad is to begin on Tuesday, with three top security officers to be tried in absentia for complicity in crimes against humanity and war crimes.

The Paris Criminal Court will try the three officials for their role in the deaths of two French Syrian men, Mazzen Dabbagh and his son Patrick, arrested in Damascus in 2013.

Tens of thousands mourned Iran's president Ebrahim Raisi on Tuesday after his death in a helicopter crash, amid political uncertainty ahead of an election for his successor next month.

Raisi and seven members of his entourage including foreign minister Hossein Amir-Abdollahian were killed when their aircraft came down on a fog-shrouded mountainside in northern Iran on Sunday.

Waving Iranian flags and portraits of the late president, mourners marched in the northwestern city of Tabriz, where Raisi's helicopter had been headed when it crashed.

Amal Clooney helped the International Criminal Court weigh evidence that led to the decision to seek arrest warrants for top Israeli and Hamas leaders, the human rights lawyer said Monday.

The high-profile British-Lebanese barrister posted a statement on the website of the Clooney Foundation for Justice, which she founded with her husband, American actor George Clooney.

Both she and the foundation had previously been criticized on social media for not speaking out over the civilian death toll in Gaza.

The women's tennis tour (WTA) on Monday announced "a multi-year partnership" with the Saudi Arabian sovereign wealth fund (PIF), emulating a deal made by the men's tour (ATP) in February.

The WTA said in a statement that it shared with PIF an "ambition to grow women's professional tennis and inspire more women and girls around the world to take up the game."

Israeli Defence Minister Yoav Gallant, whose arrest warrant was sought at the International Criminal Court on Monday, was long a staunch ally of Prime Minister Benjamin Netanyahu but has become a vocal critic.

While the former general remains grimly committed to destroying Hamas over its October 7 attack, he has clashed with Netanyahu on the issue of Gaza's post-war governance.

The United States said Monday that arch-enemy Iran sought assistance over a helicopter crash that killed president Ebrahim Raisi, as Washington meanwhile offered condolences despite saying he had "blood on his hands."

The State Department said Iran, which has had no diplomatic relations with Washington since the aftermath of the 1979 Islamic revolution, reached out afer Raisi's aging chopper crashed in foggy weather Sunday.

"We were asked by the Iranian government for assistance," State Department spokesman Matthew Miller told reporters.