Reza Zarrab—the Turkish-Iranian businessman said to have links to Turkish President Recep Tayyip Erdogan and his family—who is accused of masterminding an extensive conspiracy to help Iran evade US sanctions, has pleaded guilty and will testify against former Halkbank deputy general manager Hakan Atilla, a US prosecutor said on November 28.

The Turkish lira (TRY) completed a drop of 1.5% to 3.9630/USD against the dollar after the news and the main stock exchange index, the BIST-100, closed by 2.5% lower. The 10-year government bond yield, however, declined to 12.47% from the previous day’s 12.67%.

The lira—also under pressure because market participants perceive that the central bank is under political pressure from Erdogan not to introduce a badly needed interest rates hike—was trading at 3.9524 per dollar as of 1200 local time on November 29.

Zarrab is set to describe a multi-billion-dollar international money laundering scheme from the inside perspective, Assistant US Attorney David Denton said during his opening statement in a New York court. “Zarrab would provide the means, Atilla would provide the method,” Denton said referring to the money laundering, according to Reuters.

According to court documents, Zarrab, portrayed in a November 27 NBC News report as a flashy businessman with a pop star wife, pleaded guilty as far back as October 26.

Atilla’s lawyer Victor Rocco told the jury in his opening remarks that Zarrab bribed other people to further his scheme, including the former head of state-owned Halkbank Suleyman Aslan, and the former economy minister Zafer Caglayan, but never bribed Atilla. Erdogan, who has pushed hard to get the US to drop the case, is not accused of any crime.

“Atilla is just another one of Reza Zarrab’s many victims," Rocco said. "A hapless and helpless pawn.” Rocco, according to Bloomberg, pointed the finger directly at Aslan. "There’s no evidence that Hakan Atilla was ever bribed," Rocco said. "Not a scintilla, unlike his boss, who was paid millions of dollars in bribes."

In September, US prosecutors charged Caglayan and Aslan with conspiring to evade US sanctions against Iran.

Denton said that the prosecutors’ other witnesses would include a former Turkish law enforcement officer who participated in a Turkish investigation into the alleged money laundering scheme in 2013.

Erdogan, then prime minister, dismissed the 2013 graft probe as a plot orchestrated by US-based self-exiled cleric Fethullah Gulen to topple his government.

In the corruption case as presented in Turkey, Zarrab was accused of heading a network that bribed several ministers and other state officials to facilitate gold trading for oil with Iran via Halkbank in breach of international sanctions.

In October 2014, Turkish prosecutors dropped the case and dismissed charges against 53 people implicated in the corruption probe. Zarrab was released after spending 70 days in prison. He was seized in the US last year while he was en route to a family vacation at Disney World in Florida.

The trial [in New York] is a “theatre” staged with the help of Gulen, the AKP party spokesperson Mahir Unal said on November 28, according to Hurriyet Daily News.

“US judicial officials are cooperating with Gulen against Turkey. We know who has staged this play and what its aim is,” he added.

Ankara holds Gulen and his followers responsible for last year’s failed coup attempt. Gulen, who lives in rural Pennsylvania, strenuously denies any involvement.

Zarrab is expected to testify as a government witness in the trial of Atilla on November 29, according to the New York Times.