Reuters/Doha

Turkish President Tayyip Erdogan said on Wednesday no one had the right to "slander" Turkey by accusing it of buying oil from Islamic State, and that he would stand down if such allegations were proven to be true.

Erdogan, who was speaking at Qatar University in Doha, said he did not want relations with Moscow to worsen further.

"Nobody has the right to slander Turkey by saying Turkey is buying Daesh oil," he said.

Russia's defence ministry said it had proof that Erdogan and his family were benefiting from the illegal smuggling of oil from Islamic State-held territory in Syria and Iraq.

Government officials described the claims as baseless, while a senior official from the ruling AK Party founded by Erdogan said they were part of a narrative being spun for a Russian domestic audience.

Relations between the two hit their worst in recent memory after Turkey downed a Russian jet near the Syrian border last week, prompting Moscow to impose a raft of sanctions on Ankara.  

At a briefing in Moscow, defence ministry officials displayed satellite images which they said showed columns of tanker trucks loading with oil at installations controlled by Islamic State in Syria and Iraq, and then crossing the border into neighbouring Turkey.

The officials did not specify what direct evidence they had of the involvement of Erdogan and his family, an allegation that the Turkish president has vehemently denied.