France, Dec 01 (ANI): Russian President Vladimir Putin has said that the reason Turkey downed a Russian warplane last week was that it wanted to protect supplies of oil from Islamic State. Putin, speaking at the global climate conference in Paris, added that the decision to shoot down the plane was a "huge mistake" adding he had not met Turkish President Tayyip Erdogan, despite them both being in Paris. Relations between Russia and Turkey have nosedived since Turkey shot down the Russian bomber near the Syrian-Turkish border on Nov. 24. Putin on Saturday (November 28) signed a decree imposing economic sanctions on Turkey, while Erdogan has said Turkey will not apologise over the incident.