The increasingly nasty spat between Russia and Turkey has highlighted their alleged links to ISIS

Russia’s defence ministry proclaimed on Wednesday that it had proof that Turkey’s president “and his family” had profited from the illegal smuggling of oil from Islamic State-held territory in Syria and Iraq.

The state-run Turkish news agency Anadolu was quick to counter. It tweeted a link to an article entitled, “Syrian regime’s oil links to Daesh,” referring to an moniker for the terror group. The story included details about the Russian-backed Syrian regime’s links to the Islamic State oil trade.

Last week, Russia suspended its visa-free travel agreement with Turkey and advised that Russians avoid travelling to the NATO-member country, due to “the critical mass of terrorist incidents on Turkish soil.”

For its part, Turkey announced on Wednesday that it had detained seven Russians on the southern border with suspected links to ISIS who would be deported back to Russia.

This war of words between Russian and Turkish officials was triggered by Turkey’s downing of a Russian warplane last week, the aftermath of which has produced an increasingly nasty back and forth.

Turkish president Tayyip Recep Erdogan and Russian President Vladimir Putin have yet to meet in person to discuss the incident. But that has not stopped them from accusing each other of having ties to the Islamic State, also known as ISIS, ISIL, or Daesh.

Even as Russia and Turkey both deny the accusations, evidence suggests that both nations have harbored ties to the Islamic State since the Syrian civil war erupted nearly five years ago.

‘Undeniable’ links

Last Tuesday, Putin fired the first shot in the immediate aftermath of the jet’s downing. He denounced Turkey as an “accomplice of terrorists,” adding that Russia “established a long time ago that large quantities of oil and oil products from territory captured by Islamic State have been arriving on Turkish territory.”

Erdogan has denied the claims, saying that he would resign if Russia was able to prove that Turkey had economic or intelligence ties to ISIS. He called the accusations “slander” on Wednesday, and he warned Russia not to “play with fire.”

In July, however, Martin Chulov of The Guardian reported that a US-led raid on the compound housing the Islamic State’s “chief financial officer” produced evidence that Turkish officials directly dealt with ranking ISIS members.

The officer killed in the raid, Islamic State official Abu Sayyaf, was responsible for directing the terror army’s oil and gas operations in Syria. ISIS earns a reported hundreds of millions of dollars per year selling oil on black markets, but estimates vary.

Documents and flash drives seized during the Sayyaf raid reportedly revealed links “so clear” and “undeniable” between Turkey and ISIS “that they could end up having profound policy implications for the relationship between us and Ankara,” a senior Western official familiar with the captured intelligence told The Guardian.

Turkey joined the US-led anti-ISIS coalition in late July, after a suicide bomber with links to the terrorist group killed 32 activists in the southeastern border town of Suruc.

But the NATO ally has long been accused by experts, Kurds, and even Vice President Joe Biden of enabling ISIS’ rise by turning a blind eye to the vast smuggling networks of weapons and fighters during the ongoing Syrian war.

The move by the ruling AKP party to largely leave ISIS alone was apparently part of ongoing attempts to trigger the downfall of Syrian President Bashar al-Assad’s regime and to serve as a foil to the Kurds, who Turkey has long perceived as a bigger threat to its sovereignty than the Islamic State.

Ankara officially ended its loose-border policy last year, but not before its southern frontier became a transit point for cheap oil, weapons, foreign fighters, and pillaged antiquities.

The effects of that policy are still being felt: The Wall Street Journal reportedlast week that the Obama administration has been pressuring Turkey to send additional troops to its southern border with Syria to close a 60-mile “gap” that is still being used by ISIS to transport fighters and weapons.

In October, an ISIS-linked suicide bomber killed more than 150 people at a peace rally in Ankara.

Assad’s payroll

Russia, meanwhile — a staunch ally of Assad — began launching airstrikes in Syria in late September on behalf of the Syrian government, under the guise of fighting ISIS.

But Russia has been accused of striking ISIS strongholds only sparingly and disproportionately targeting non-ISIS rebel brigades battling Assad’s forces in western and central Syria. It’s a move experts say is in line with Assad’s cynical plan to leave ISIS standing so that the international community is forced to choose between his regime and the jihadists.

Moreover, the lifelines Russian actors have thrown to Assad — and, by extension, to ISIS — have not been limited to military aid.

The Telegraph reported in May that the Russian-backed Syrian regime not only had oil ties to ISIS, but that the ties were directly controlled by Assad.

“Other oil and gas fields in ISIL’s hands are thought to be operated by personnel who remain on the payroll of the regime’s oil ministry,” The Telegraph reported. “The oil is then sold to Mr Assad, who distributes it in areas he controls at relatively low prices, helping him to win the loyalty of local people.”

That same month, the US Treasury Department sanctioned Moscow-based Tempbank. It also leveled sanctions on Mikhail Gagloev, one of the bank’s senior executives, for providing material support and services to the Syrian government, including the Central Bank of Syria and SYTROL, Syria’s state oil marketing firm.

And just last week, the Treasury Department sanctioned Russian-Syrian businessman George Haswani last week for allegedly using his firm, Hesco Engineering and Construction Co., to purchase oil from the Islamic State on behalf of the Assad regime.

Kirsan Ilyumzhinov, a former president of the autonomous Russian Republic of Kalmykia, was sanctioned in the same round on suspicion of helping Syria’s central bank avoid international sanctions.

Russia, for its part, responded to last week’s round of sanctions by saying that Washington should stop playing “geopolitical games.”

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