President Recep Tayyip Erdogan on Friday blasted as "laughable" Russia's accusation that Turkey was actively preparing to invade Syria.

"I find this Russian statement laughable... rather it is Russia that is currently engaged in an invasion of Syria," Erdogan said, quoted by the state-run Anatolia news agency.

Russia on Thursday had claimed Turkey was planning to invade Syria, saying it had spotted troops and military equipment on the border with the war-torn country.

"We have serious grounds to suspect Turkey is in intensive preparations for an armed invasion of the territory of a sovereign state -- the Syrian Arab Republic," Russia's defence ministry said in a statement.

Ties between Moscow, which supports the regime of Syrian President Bashar al-Assad, and Ankara, which is a staunch backer of the opposition, have been in tatters since Turkey shot down a Russian warplane on the Syrian border in November, claiming it had entered Turkish airspace.

Following a request from Assad, Moscow launched a bombing campaign in Syria in September, saying it needed to target jihadists like the Islamic State group before they cross into Russia. But air strikes have also hit the rebels opposed to Assad.

Tens of thousands of Syrians were apparently streaming towards Turkey on Friday as regime troops pressed a major Russian-backed offensive around Aleppo.

Related Story