Turkey challenges Russia for proof over IS oil trade allegations

Turkey has challenged Russia to prove its claim that Turkish forces shot down a Russian plane in order to protect its oil trade with the so-called Islamic State (IS), the BBC reports. 

Responding to a statement by Russian President Vladimir Putin, Turkish President Recep Tayyip Erdogan said that if you allege something you should prove it.

Relations between the two countries deteriorated after a Russian jet was downed by Turkish forces as it was flying over Syria last week.  Turkey has insisted that the plane entered its airspace and was warned to leave.

In the incident, one Russian pilot was killed and the other rescued, and a Russian marine was killed during the rescue operation in north-western Syria.

Russia has insisted the plane did not cross the border and that it gave advance notice of the flight path to the US, Turkey's ally. However, the US has supported Turkey's version of events.

"You should put your documents on the table if you have any. Let's see the documents," the BBC reports Erdogan saying.

"We are acting with patience. It is not positive for the two countries which have reached a position which could be regarded as a strategic partnership to make emotional statements."

Erdogan also vowed to step down if the allegation that Turkey was buying oil from IS proved true, suggesting that Putin should do the same if he was wrong.

Russia has been carrying out air strikes in Syria, targeting rebels against Syrian President Bashar al-Assad, including IS, but Turkey remains a vehement opponent of Assad.

Russia has imposed sanctions on Turkey over the downing of the plane, including restrictions on imports of Turkish food and an end to visa-free travel.

The BBC adds that IS earns much of its money from illegal sales of oil, but Turkey has staunchly denied that it is involved in the trade.

"We have every reason to think that the decision to shoot down our plane was dictated by the desire to protect the oil supply lines to Turkish territory," Putin said at a news conference in Paris on Monday.