Turkey shooting down Russia’s fighter jet proves Ankara supports terrorism, says a Syrian military source Tuesday.

The source also said that gunning down the Russian Sukhoi Su-24 proves Turkey provides all forms of support to terrorist organizations in Syria, which are otherwise collapsing because of strikes from the government forces.

In a statement to SANA news agency, the military source condemns Turkey’s decision to shoot the Russian jet down and calls it a “gross violation of the Syrian sovereignty.”

“The desperate acts of aggression will only increase our determination to continue the war against the terrorist organizations with the support and help of Syria’s friends, mainly Russia,” the Syrian army official said in the statement.

Meanwhile, the Russian defense ministry has suspended military cooperation with Turkey, Al Jazeera reported. Russian Foreign Minister Sergei Lavrov cancelled his trip to Turkey after the Turkish military had gunned down the Su-24 near the Turkey-Syria border. Russia has advised its citizens against traveling to Turkey, calling the Middle Eastern country “unsafe.”

Russian President Vladimir Putin compared Turkey’s action to being “stabbed in the back.” "Today's loss is linked to a stab in the back delivered to us by accomplices of terrorists. I cannot qualify what happened today as anything else," Putin said in a televised statement.

"Instead of immediately establishing contacts with us, as far as we know Turkey turned to its NATO partners to discuss this incident - as if we had hit their plane and not the other way around."

Turkish PM Ahmet Davutoglu, on the contrary, said his country defended its borders. "Turkey will not hesitate to take all steps to protect the country's security," he said.