Russia has now hit out at the family of Turkish president Recep Tayyip Erdogan stating the entire family was benefiting from its oil-business links with the Islamic State (Isis).

The allegation has once again put the focus on Turkish president's son Bilal Erdogan, whose ships it is claimed are selling the Isis oil into the black markets.

Russian deputy defence minister on Wednesday made an explosive statement that the Turkish president Recep Tayyip Erdogan and his family are involved in oil trade with the Islamic State (Isis) terrorists.

Anatoly Antonov told  Russia's Interfax news agency that Russia now has evidence to show that Erdogan and his family personally benefit from oil transactions with Isis.

"Turkey is the main consumer of the oil stolen from its rightful owners, Syria and Iraq. According to information we've received, the senior political leadership of the country - President Erdogan and his family - are involved in this criminal business," said Antonov.

"Maybe I'm being too blunt, but one can only entrust control over this thieving business to one's closest associates."

"In the West, no one has asked questions about the fact that the Turkish president's son heads one of the biggest energy companies, or that his son-in-law has been appointed energy minister. What a marvelous family business!"

While Russia previously on several occasions since the downing of its jet on 24 November has accused Turkey of having links with Isis and Turkey, this is the first time that an allegation has been launched against Erdogan's family.

The claim now once again has reignited the rumours that the Isis oil smuggled from Syria and Iraq was being sold to buyers into the black market by a company owned by Bilal Erdogan, the son of the Turkish president.

A 2014 report published in a Turkish daily, had revealed that ships owned by Bilal Erdogan were transporting Isis oil from Syria.

The report said that  BMZ Group, which belongs to Bilal was  behind the smuggling of helping the Isis was "converting millions of barrels of Syrian oil into hundreds of millions of dollars of Islamic State revenue."

Previously there also have been reports that Sumeyye Erdogan, the daughter of the Turkish president was running a 'covert' hospital exclusively to treat wounded Isis in the southeastern Turkish city of Sanliurfa.