A Turkish prosecutor has demanded that arrest warrants be issued against two Saudi nationals close to Crown Prince Mohammed bin Salman over the murder of journalist Jamal Khashoggi, a Turkish source close to the investigation said Wednesday.

The poorest country in the Middle East, Yemen is bogged down in war and the scene of the worst humanitarian crisis in the world today.

Yemeni government representatives were expected to join a rebel delegation in Sweden on Wednesday for high-stakes peace talks aimed at ending four years of devastating war.

Two key U.S. Republican senators said Tuesday that they have "zero" doubt that Saudi Arabia's crown prince was complicit in the murder of the journalist Jamal Khashoggi, contradicting President Donald Trump's more neutral position.

A rebel delegation flew out of the Yemeni capital Tuesday accompanied by a U.N. peace envoy, heading for high-stakes talks in Sweden with the government aimed at ending the country's devastating war.

The humanitarian crisis in Yemen, already the world's worst, will deteriorate in 2019, the UN said Tuesday, warning that the number of people needing food aid is set to jump by four million. 

Yemen's Saudi-backed government and the Huthi rebels have agreed to exchange hundreds of prisoners ahead of planned peace talks in Sweden, sources said Tuesday.

The deal covers between 1,500 and 2,000 members of the pro-government forces and between 1,000 and 1,500 rebels, government official Hadi Haig told AFP.

CIA director Gina Haspel has agreed to brief a "small group" of US lawmakers about the murder of Saudi journalist Jamal Khashoggi, the chair of the Senate foreign relations committee said Monday.

Proposed UN-led talks in Sweden mark a "critical opportunity" to bring peace to war-torn Yemen after four years of conflict, a top Emirati official said Tuesday.

Algeria's President Abdelaziz Bouteflika called off a meeting with visiting Saudi Crown Prince Mohammed bin Salman on Monday because of ill health, the national news agency APS reported.