AFP: Russia warns Turkey will regret plane downing, receives condolences

Russian President Vladimir Putin on Thursday vowed that the Turkish leadership would be made to regret the downing of one of Moscow's warplanes, as Ankara presented its condolences for the death of a Russian pilot in the incident, according to AFP.

Moscow announced a halt to talks on a major gas pipeline with NATO member Ankara as Putin fired another salvo in their war of words and Turkish leader Recep Tayyip Erdogan shot back by claiming he had "proof" Russia was involved in illegal oil trading with the Islamic State group, Yahoo! News reported with reference to AFP.

Following talks with Russian Foreign Minister Sergei Lavrov in Belgrade in the highest bilateral level contact since the crisis began, Turkish Foreign Minister Mevlut Cavusoglu presented his condolences for the death of a Russian pilot in the incident.

But he stopped short of issuing the apology that Moscow has demanded and admitted that there had been no breakthrough in the 40-minute talks on the sidelines of a security conference.

Russia and Turkey have been plunged into their worst crisis since the Cold War over Turkey's downing of a Russian jet on its border with Syria on November 24 – sparking fury and economic sanctions from the Kremlin.

Russia has accused Erdogan and his family of personally profiting from the oil trade with IS, which controls a large chunk of Syrian territory including many oil fields.

"We will not forget this complicity with terrorists. We always considered and will always consider treachery to be the ultimate and lowest act," Putin told lawmakers in his annual state of the nation speech.

"We know for example who in Turkey fills their pockets and allows terrorists to make money from the stolen oil in Syria."

Erdogan has furiously denied the accusations against him and his family and said Turkey had proof that Russia was, in fact, involved in trading oil with IS.

"We have the proof in our hands. We will reveal it to the world," the Turkish leader said in a televised speech in Ankara.