The United Arab Emirates pulled out of the air campaign fighting Islamic State militants after the capture of a Jordanian pilot who has since been killed by the extremists, the New York Times reported Wednesday.

The pilot was captured in December and Islamic State militants released a video Tuesday showing the man in a cage being burned alive.

Kuwait appeals court on Monday upheld a four-year jail sentence against an online activist for insulting judges on Twitter, according to the court ruling.

A lower court in October handed the jail term against Ahmad Fadhel who was charged with writing comments on Twitter deemed offensive to a number of judges, who then sued him.

Kuwait's lower court Sunday sentenced a stateless activist for five years in jail for allegedly insulting the ruler of the oil-rich Gulf state, his lawyer said.

Khaled al-Kafeefa told AFP that defendant Abdullah al-Enezi, who has apparently fled the country, was not present in court for the ruling.

French Foreign Minister Laurent Fabius called Tuesday for international cooperation against extremism, saying Muslims have been the first victims of "terrorism".

"No one fights under the name of religion," Fabius told journalists in Kuwait, the first Muslim country he has visited since last month's deadly attack by Islamist gunmen on French magazine Charlie Hebdo.

U.S.-led aircraft hammered Islamic State militants in northern Iraq over the past 24 hours, the American military said Thursday, as Kurdish forces pressed an offensive against the jihadists in the area.

U.S. and coalition bombers, fighter jets and drones carried out a total of 31 air raids since Wednesday morning, including ten in Syria and 21 in Iraq, according to the American military command overseeing "Operation Inherent Resolve" out of headquarters in Kuwait.

Oil prices are unlikely to fall further after a plunge of nearly 60 percent since June, Iraqi Oil Minister Adel Abdul Mahdi said on Wednesday.

"Our estimate is that the prices (of oil) have reached the bottom. It is very difficult to drop lower than this," Abdul Mahdi told a conference in Kuwait.

Kuwait has scrapped the commercial license of leading newspaper al-Watan, which has been highly critical of the government, citing its failure to comply with legally required financial terms.

Al-Watan, owned by a member of the al-Sabah ruling family, said on its website, which was still operating, that it had challenged the decision in court.

Kuwait will host a third donors conference to raise funds for U.N. humanitarian operations in war-torn Syria, the foreign minister said on Sunday.

Sheikh Sabah Khaled al-Sabah told reporters Kuwait would host the meeting at the request of U.N. chief Ban Ki-moon but that timing was still being worked out.

Kuwait said Tuesday that the sharp fall in world oil prices is unjustified but that the market may not improve before the second half of this year.

"Nobody can justify the drop now," Oil Minister Ali al-Omair told reporters as prices slid towards six-year lows.

Arab League chief Nabil al-Arabi “strongly” condemned Sunday the twin suicide bombing that killed nine people Saturday in Tripoli's Jabal Mohsen, on the eve of an expected “solidarity” visit by an Arab ministerial delegation to Lebanon.

In a statement released by his office, Arabi also lauded “the stances and wisdom of all the Lebanese political leaders who condemned this abhorrent crime.”