Turkey is ready to take any measures against threats to its national security from war-torn Syria, its foreign minister warned Wednesday.

"The Turkish republic is a powerful state and never hesitates to take any measures to protect its national security if need be," Foreign Minister Ahmet Davutoglu told AFP in an exclusive interview.

When asked by AFP, he did not rule out the possibility of cross-border operations into the neighbouring country.

"Any group in Syria, or the regime, should not test Turkey's determination," said the minister, speaking in his central home province of Konya.

Turkey, which backs the three-year-old uprising against Syrian President Bashar al-Assad and hosts many refugees, on Sunday shot down a Syrian fighter jet that it said had breached its airspace.

It has also warned it will protect a historic shrine that is under Turkish jurisdiction but located inside Syria's northern Aleppo province against threats from Islamist militants.

A Turkish flag flies over the Tomb of Suleyman Shah, grandfather of Ottoman Empire founder Osman, and a small garrison with a symbolic number of troops is permanently stationed there.

The site, located 25 kilometres (15 miles) from the border, has been threatened by the extremist group Islamic State of Iraq and the Levant (ISIL).

Davutoglu accused ISIL of clashing with Free Syrian Army rebels while refraining from attacking regime forces.

"Turkey is ready to take any legitimate step under international law if its national security, including the area where the tomb of Suleyman Shah is situated, is threatened," he said.

- 'Bloody civil conflict' -

Once warm relations between Syria and Turkey have collapsed since the conflict erupted in 2011, with Ankara squarely backing the rebels and hosting more than 750,000 refugees, mostly in camps along the border.

"The Syrian regime first of all must put an end to this hostile stance and barbarian methods," said Davutoglu.

"Which regime can have the right to drop barrel bombs, Scud missiles and chemical weapons against its own people?" he asked.

Tensions have flared since Sunday's jet downing, which Syria labelled "flagrant aggression".

On Monday, Turkey's military reported a dozen incidents involving its aircraft and Syrian anti-aircraft defences.

Turkish Prime Minister Recep Tayyip Erdogan, a vocal critic of Assad, praised Turkey's military for shooting down the Syrian warplane.

It was the most serious incident since Turkish jets last September shot down a Syrian helicopter that Ankara said was two kilometres inside its airspace.

Turkey toughened its rules of engagement after the downing of one of its own fighter jets by the Syrian air force in June 2012, declaring any military approach of the border from Syria would be considered a threat.

"Turkey's rules of engagement are not a secret," said Davutoglu. "They were not declared only to remain on paper... we have tried to prevent tension and conflict, but the Syrian side dared to test our deterrence."

Local media have meanwhile reported that Turkey has deployed elite units on the border.

The minister said the military was able to "immediately respond in case of any violation", with the air force constantly patrolling and ground troops prepared to protect borders.

"There can be nothing more natural than this," he said. "Literally, one of the bloodiest civil conflicts of the last century is taking place in Syria."