The UN's envoy on Syria is meeting with Turkish Foreign Minister Ahmet Davutoglu on Saturday to discuss the 19-month-long Syrian civil war.
Lakhdar Brahimi travelled to Istanbul from Saudi Arabia amid growing tensions between Syria and its northern neighbour Turkey.
On Wednesday, Turkey intercepted a Syrian passenger plane en route from Moscow to Damascus and seized what it said was military equipment on board.
Syria denounced the move as air piracy and Russia has said the cargo was radar parts that complied with international law.
Tensions between Damascus and its larger neighbour have soared since a shell fired from the Syrian side killed five Turkish civilians in a border village on October 3.
The Syrian army has been battling to restore its supply lines between the capital and second city Aleppo since rebels captured a key town on the main highway earlier this week
Mr Davutoglu will also meet separately in Istanbul with Arab leaders and German Foreign Minister Guido Westerwelle later.
The news comes as Turkey's foreign minister, Ahmet Davutoglu, has warned his country will - in his words - "retaliate without hesitation" if its border with Syria is violated again.
Turkey's armed forces have repeatedly responded in kind over the past few weeks to gunfire and shelling spilling across the border from Syria and have warned of a more forceful response if the violence is not contained.
