The EU's chief diplomat Catherine Ashton strongly condemned on Thursday Syria’s shelling of a Turkish border village, urging both countries to show restraint.
“Yesterday’s incident clearly shows the tragic side effect of the Syrian crisis on neighboring countries,” she said in a statement to RIA Novosti.
The Syrian military fired artillery late Wednesday over the border into southeastern Turkey, killing five people and wounding nine. Turkey responded by bombing the area from which the shelling took place.
The incident threatens to further inflame tensions in the region and sparked fears that the months-long violent conflict may drag other countries into the civil war.
A NATO official also condemned the attack, warning of an imminent security threat to the alliance, of which Turkey is a member.
“The recent acts of aggression from the Syrian regime on the southeastern border of NATO is a flagrant violation of international law and represents a clear and present danger to one member,” the official told RIA Novosti.
NATO chief Anders Fogh Rasmussen has repeatedly stated, however, that NATO would avoid involvement in the Syrian conflict.
The Turkish parliament convened an emergency, closed-door session on Thursday to provide Turkish Prime Minister Teyyip Erdogan with a one-year mandate that approves cross-border military action.
The Turkish authorities were quick, however, to note the step is not a declaration of war.
Damascus, for its part, has expressed its condolences to the families of those killed in the shelling.
Ankara had earlier appealed to the UN Security Council to force Syria into respecting Turkish sovereignty.
The conflict in Syria, between anti-regime rebels and government forces, has raged since March 2011 and has claimed around 20,000 lives, according to UN estimates.