Russian President Vladimir Putin and Turkish President Recep Tayyip Erdogan
Russian President Vladimir Putin and Turkish President Recep Tayyip ErdoganReuters

EU foreign policy chief Federica Mogherini warned on Tuesday that Russia and Turkey are headed towards a "hot war," as she voiced concerns that the growing tensions between the two on the Syrian border risk spilling over into open warfare.

Speaking at a debate at the European Parliament's Foreign Affairs Committee in Brussels, Mogherini said, "we are always referring to Syria as a proxy war among regional actors. This risks to become something bigger than this."

"I'm not thinking of a cold war. No, we risk a hot war among different actors than the one we always think of. Not necessarily Russia and the United States, but Russia and Turkey, could be," she said.

"As Europeans, we have a clear interest in trying to contain and scale down the tensions."

Mogherini's statements come in the wake of a ceasefire in Syria announced by the US and Russia which is to go into effect on Saturday. There remain huge doubts over the implementation of the deal, as it does not take into account Islamic State (ISIS) or Al Qaeda's Syrian affiliate Nusra Front, which Russia could continue striking.

Her comments also come as US Secretary of State John Kerry warned Tuesday that if Russia and the Syrian regime are not serious about a political transition, he has a "Plan B" that likely would consist of a military escalation.

Russia has been conducting airstrikes on the ISIS and Nusra Front as well as Western-backed rebel forces since last September, to prop up the regime of its ally Bashar al-Assad. Iran has likewise been militarily involved to keep Assad in power.

Tensions between Russia and NATO-member Turkey have been high, ever since Turkey shot down a Russian Su-24 jet on the Syrian border on November 24, killing two Russian officers. In response, Russia issued vast sanctions on Turkey dealing serious financial damage.

Russia has also been spying on Turkey from the border, and has warned that if Turkey and Saudi Arabia follow through on their statements hinting at a ground offensive in Syria, it would cause a "world war."

Highlighting the growing military standoff between the two, Russia in December deployed its Mosvka missile cruiser off the coast of Syria. While the ship was said to be there to aid the airstrike campaign against Syrian rebels, its arsenal includes nuclear-capable Vulkan missiles designed to sink other warships - indicating the deployment was likely meant as a message to Turkey instead.