The U.N. Security Council warned in a unanimously adopted statement Wednesday of a risk of "dispersion" of jihadist prisoners in Syria, but stopped short of calling for a halt to Turkey's offensive against Kurdish forces there.

Two Belgian jihadists have escaped from detention in northeast Syria since Turkey launched an offensive against Kurdish forces in the region, the head of the national anti-terrorist agency said Wednesday.

Turkish President Recep Tayyip Erdogan on Wednesday firmly ruled out any negotiations with Kurdish militants in Syria, saying their only option was to lay down arms and retreat.

The Syrian army deployed alongside Kurdish forces on the front line in northern Syria Wednesday but their newfound cooperation saw no let-up in the week-old Turkish invasion, a monitor said.

Kuwait's ruler Emir Sheikh Sabah al-Ahmad Al-Sabah returned home Wednesday after undergoing medical tests in the United States, according to the official KUNA news agency.

Turkey rebuffed international pressure to curb its military offensive against Kurdish militants in Syria on Wednesday as US President Donald Trump dispatched his deputy Mike Pence to Ankara to demand a ceasefire.

Pakistani Prime Minister Imran Khan met Saudi Arabia's King Salman on Tuesday, Saudi state media reported, two days after he visited Iran on a mission to defuse tensions between Riyadh and Tehran.

Tensions have soared in the Gulf in recent months with a series of attacks on oil infrastructure and tankers which have raised fears of a war between the arch-rivals.

Russian President Vladimir Putin discussed the conflict in Syria in a phone call with Recep Tayyip Erdogan and invited the Turkish leader to soon visit Russia, the Kremlin said.

Canada on Tuesday announced it had temporarily suspended "new export permits" to Turkey, particularly of military equipment, in response to Ankara's offensive into northern Syria.

The United States wants to maintain support for the Kurdish-led Syrian Democratic Forces (SDF) in their fight against Islamic State militants despite US troops withdrawing from northern Syria, a Pentagon official said Tuesday.