Russian President Vladmir Putin has said Turkey shot down a Russian warplane in order to protect its oil trade with Islamic State, adding that Russia had received more information showing that IS oil was going via Turkey.
President Putin said he did not meet his Turkish counterpart Recep Tayyip Erdogan at the climate change summit in Paris on Monday to discuss the downing of the jet, which he described as a "huge mistake".
Mr Putin's comments are the latest in the war of words between Russia and Turkey following the downing of the Russian jet near the Syrian border last week.
Russia announced at the weekend a series of economic sanctions against Turkey.
Turkey has shown it is willing to take on Russia after downing a Russian fighter jet.
This incident will leave the American military profoundly alarmed that the Syrian conflict is now threatening to spiral out of all control.