Turkish Prime Minister Recep Tayyip Erdogan has warned President Bashar al-Assad that his days as Syria's leader are running out.
Erdogan, speaking in Istanbul, said Assad can rely on "tanks and cannons only up to a certain point." He added, "The day will come when you'll also leave."
Tensions have been running high between Turkey and Syria as Ankara has become increasingly vocal in its criticism of Assad's crackdown on antigovernment protesters.
Earlier today, Turkish media reports said two Turkish citizens were injured when a convoy of buses carrying pilgrims came under attack in northern Syria.
The media reports cited passengers as saying the attack was carried out by Syrian soldiers at a checkpoint just across the border.
The United Nations says at least 3,500 people are believed to have been killed since the crackdown on protests began in mid-March.
Activists said at least four people were killed today as security forces carried out raids in and around the flashpoint central city of Homs.
Meanwhile, representatives from the Syrian opposition met British Foreign Secretary William Hague for the first time in London today, although Hague said it was too early for Britain to formally recognize them.
compiled from agency reports