Sen. Lindsey O. Graham (R-S.C.) thought he was talking to Turkey’s minister of defense two months ago when he offered to play a mediating role between President Trump and Turkish President Recep Tayyip Erdogan. The two countries should form a free-trade agreement, Graham suggested before rushing off to a Senate floor vote. He committed to talking to the minister again at a future date.

The person on the other line wasn’t the defense minister, however. It was a Russian radio host who has earned a reputation for getting foreign officials on the phone and eliciting information under false pretenses as he did in two calls with Graham. Those conversations, obtained and published Thursday by Politico, have been described as pranks but are much drier in content than that term would suggest. Graham’s suspicions don’t appear to have been raised because the subjects of the call were generally related to the relationship between the two countries. (Politico notes that the radio hosts have been accused in the past of ties to Russian intelligence, which they deny.)

In the second conversation, Graham touts his access to Trump by claiming to have spent significant time with the president over the previous weekend in which they discussed Turkey. During the conversation, he also introduces a subject that neither he nor the “minister of defense” broached in the first conversation.

“This case involving the Turkish bank?” Graham said. “He’s very sensitive. The president wants to be helpful within the limits of his power.”

He mentioned it again a bit later, describing his conversations with Trump during their interactions.

“He was very keen on the bank case,” Graham said. “You know the one involving the Turkish bank? He does not want that case to hurt our relationship.”

“He mentioned that twice,” he added.

The “minister of defense” doesn’t seem to understand what Graham is saying, responding with a question about how sanctions that might be imposed following Turkey’s purchase of weapons from Russia would affect Turkey’s banks.

“We don’t want to get into sanctions,” Graham said as the call was wrapping up. “We don’t want the bank case to get out of hand.”

What is this “bank case”? It appears to be a reference to a criminal case in the United States focused on a man named Reza Zarrab. Zarrab was at the center of an effort to help Iran evade international sanctions by masking money transfers into the country as sales of gold. After being arrested in the United States in 2016, Zarrab agreed to work with prosecutors, providing testimony against an official from a Turkish state bank, Halkbank. That official was found guilty in January 2018.

In late 2017, Zarrab also directly implicated Erdogan, suggesting that the then-prime minister had approved the scheme. Shortly after Zarrab was arrested, Erdogan pressured the Obama administration to release him — and to fire the U.S. attorney who brought charges against Zarrab, Preet Bharara. Trump fired Bharara in March 2017.

The corruption case surrounding Zarrab prompted a dramatic split between Erdogan and a cleric named Fethullah Gulen, who had been an Erdogan ally. Gulen was blamed for playing a leading role in the probe that brought the sanctions-evasion scheme to light and was eventually blamed for a 2016 coup attempt against Erdogan. By then, Gulen had left Turkey and was living in a compound in Pennsylvania.

Trump has repeatedly been drawn into this feud, a function of relationships involving his allies and his own sympathies for Erdogan. (As Graham told the “minister of defense”: “I think President Trump likes President Erdogan. I think he’s a strong man and we need to deal with strong people.”)

During the 2016 campaign, Trump adviser Michael Flynn — eventually Trump’s first national security adviser — did lobbying work indirectly for the Turkish government. News reports suggested that his advocacy at one point included mulling over a scheme to extradite Gulen back to Turkey. Zarrab himself has been represented by two attorneys whose names might be familiar to Americans: Michael Mukasey, a former attorney general, and Trump’s own attorney, Rudolph W. Giuliani. The pair even met with Erdogan in early 2017, reportedly to try to resolve the Zarrab case.

At some point that year, Trump directly tried to intervene. With Giuliani and Mukasey in the room, Trump reportedly asked then-Secretary of State Rex Tillerson to try to get the Justice Department to drop the case against Zarrab. The president also suggested he speak with Giuliani about the case. Tillerson refused.

Giuliani admitted to trying to work out a deal in which Zarrab might be traded for Andrew Brunson, an American pastor who was detained by Turkey on trumped-up espionage charges. (Erdogan seems to have intended that Brunson be swapped instead for the cleric Gulen, reportedly saying at one point, “Give us the priest and take this one.”)

Trump made Brunson’s release a priority in early 2018, and the pastor was released last October.

That Graham focused on the “case involving the Turkish bank” — Halkbank — after apparently spending time with Trump at his club in Bedminster in August suggests that the Zarrab affair may still be at the forefront of Trump’s concerns in regard to Turkey. It also suggests another situation where, like Ukraine, Trump may be following Giuliani’s lead.

On Sunday, Trump and Erdogan spoke by phone. The focus of the call was Syria. It’s not clear if the case of the Turkish bank was raised.

It is clear that Trump was speaking with the real Erdogan.