Israeli air strikes on east Syria killed 57 regime forces and allied Iran-backed fighters, in the deadliest such strikes since the start of the conflict, a war monitoring group said Wednesday.

The overnight raids against arms depots and military positions killed at least 14 Syrian regime forces, 16 Iraqi militia fighters and 11 Afghan members of the pro-Iran Fatimid Brigade, said the Syrian Observatory for Human Rights.

The oldest son of Oman's sultan became the first crown prince in the country's history Tuesday as the Gulf state published a new "fundamental law" stipulating the line of succession.

The foreign ministers of Egypt, Jordan, France and Germany met in Cairo Monday in the latest push to revive Israeli-Palestinian talks stalled since 2014.

The European Union on Tuesday hit out at the decision by the United States to label Yemen's Huthi rebels as "terrorists", warning it could hinder peace efforts and aid deliveries. 

A leading Israeli human rights group has begun describing both Israel and its control of the Palestinian territories as a single "apartheid" regime, using an explosive term that the country's leaders and their supporters vehemently reject.

In a report released Tuesday, B'Tselem says that while Palestinians live under different forms of Israeli control in the occupied West Bank, blockaded Gaza, annexed east Jerusalem and within Israel itself, they have fewer rights than Jews in the entire area between the Mediterranean Sea and the Jordan River.

Bahrain has accused Qatar of seizing one of the kingdom's champion bodybuilders during a fishing trip even as Manama normalised its relationship with its neighbour.

Yemen's Iran-backed Huthis on Monday condemned the United States' move to brand the rebels as a terrorist organisation and said they reserved the right to respond.

A leading aid organization on Monday warned that U.S. Secretary of State Mike Pompeo's move to designate Yemen's Iran-backed Houthi rebels as a foreign terrorist organization would deal another "devastating blow" to the impoverished and war-torn nation.

In his announcement late Sunday, Pompeo pledged that U.S. measures would help absorb the impact on aid groups and allow humanitarian assistance to continue to flow to the Arab world's poorest country.

Air travel between Qatar and Saudi Arabia will resume on Monday, according to the countries' airlines, a major landmark as Doha's former rivals normalise ties under a landmark agreement.

The United States will designate Yemen's Huthi rebels as a terrorist group, Secretary of State Mike Pompeo said Sunday, a late-term move that aid groups fear will worsen a humanitarian crisis.