Syrian ally Iran has warned their common neighbour
Turkey that it will meet a harsh response should Ankara carry out any strikes inside Syrian territory, a pro-Damascus daily reported on Monday.
"Any attack on Syrian territory will meet with a harsh response, and the Iranian-Syrian mutual defence agreement will be activated," the Al-Watan newspaper said.
"Turkey has received very strong warnings in the past few hours and the following message -- beware changing the rules of the game," the paper added.
Iran is the closest regional ally of embattled Syrian President Bashar al-Assad, but has also striven to keep good relations with Turkey even as the standoff over its controversial nuclear programme has deepened with other NATO member states.
Tehran has enjoyed close ties with Damascus since 1980 when the Syrian government took its side in its devastating eight-year war with now executed dictator Saddam Hussein's regime in Baghdad, and has signed a series of defence pacts, including in 2006 and 2008.
But Ankara has been a leading champion of the more than 16-month uprising against the Assad regime and has given refuge to large numbers of army defectors, who have formed the kernel of a rebel army, as well as tens of thousands of civilian refugees.
Al-Watan cited an "Arab diplomat" as accusing Turkey of seeking to use its fears about the rebel Kurdistan Workers' Party (PKK), which already enjoys rear-bases in the far north of Iraq, as a pretext to intervene in Syria.
"Ankara is preparing an agreement with Washington to intervene militarily in the Syrian (crisis), using the Kurdish card as an excuse," the paper said.
"Turkey has agreed with the United States on a military intervention limited to the north of Syria, specifically the northern province of Aleppo, to pave the way for the creation of a safe haven guarded by the armed gangs."
Turkish newspapers have reported that some Kurdish-majority regions of northern Syria have been flying the flag of Syria's PKK ally, the Democratic Union Party (PYD), in what they have said is a deal with the Assad family's government, which was a longtime backer of the Kurdish rebel group's insurgency in Turkey.
Turkish Prime Minister Recep Tayyip Erdogan has warned that it is a "given" that Turkish troops would pursue fleeing PKK militants inside Syria, warning that Ankara would not hesitate to strike "terrorists."
Turkey has sent a convoy of tanks, ground-to-air missile batteries and other weapons to the border with Syria to further bolster its forces, the Anatolia news agency reported on Monday.
Turkey has repeatedly carried out air and ground operations against suspected PKK rear-bases in northern Iraq. Iran has also done so against suspected hideouts in the same area of PKK ally the Party of Free Life of Kurdistan (PJAK).