(Bloomberg) -- President Donald Trump repeatedly pressed then-Secretary of State Rex Tillerson for help getting a criminal case dropped against a client of Rudy Giuliani, long after the top U.S. diplomat made clear he felt the idea was inappropriate, said two people familiar with the matter.

Tillerson grew increasingly frustrated with the president’s multiple requests in 2017 that he pressure the Justice Department or agree to a broader political bargain being put forward by Giuliani, according to the people.

Through much of the year, Giuliani floated a plan to swap Reza Zarrab, a Turkish-Iranian gold trader, for Andrew Brunson, a U.S. evangelical pastor being held in Turkey.

Tillerson insisted that the case against Zarrab, which was before the Southern District of New York, was a matter for the courts and should be allowed to run its course. His refusal left Trump increasingly frustrated, and there was deep friction between the two over the issue, one of the people said.

Objections Registered

On Wednesday, Bloomberg News reported that Trump pressed Tillerson in an Oval Office meeting in the second half of 2017 to help get the case against Zarrab dropped. After the encounter, Tillerson pulled then-Chief of Staff John Kelly aside in a hallway and reiterated his objections, saying the request was illegal.

The New York Times later reported that Giuliani and former Attorney General Michael Mukasey, who were both working for Zarrab, made their case in a prior meeting with Trump and Tillerson in early 2017, months after Trump’s inauguration.

Another person familiar with the events at the time said Giuliani even showed up unannounced at the Justice Department and requested a meeting with top officials to discuss the case. The Department never seriously considered the idea of the prisoner swap, the person said.

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The latest reporting shows that the specific episode wasn’t isolated and that the president remained concerned with the Zarrab case, which was a high priority for both Trump and Turkish President Recep Tayyip Erdogan.

Swap Sought

In a phone interview earlier this week, Giuliani -- who became one of Trump’s personal lawyers in April 2018 -- initially denied he’d ever raised Zarrab’s case with the president, but later said he might have done so. He acknowledged he spoke with U.S. officials as part of his effort to arrange a swap of Zarrab for Brunson, who was eventually freed in 2018.

Zarrab was being prosecuted on charges of evading U.S. sanctions against Iran’s nuclear program. He’d hired Mukasey and Giuliani, who’s said he reached out repeatedly to U.S. officials to seek a diplomatic solution for his client outside the courts.

After his arrest in Miami in early 2016, prosecutors alleged Zarrab had “close ties” with Erdogan. They accused him of using his network of companies to move money through the U.S. financial system with the goal of helping Iran evade sanctions as the U.S. was stepping up economic pressure on Tehran.

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Zarrab later pleaded guilty and testified against Mehmet Hakan Atilla, who headed international banking at state-owned Turkiye Halk Bankasii AS, known as Halkbank. Zarrab said Erdogan knew of and supported the laundering effort on behalf of Iran. Erdogan and other senior Turkish officials repeatedly rejected the accusations, saying they were fabrications.

Atilla was eventually convicted of helping Iran evade economic sanctions on billions of dollars of oil revenue and served 28 months in U.S. prison.

Tillerson, the former chief executive officer of oil giant Exxon Mobil Corp., was fired by Trump in a March 2018 tweet. At a forum with Bob Schieffer of CBS News in December, he said the president frequently asked him to do things that were illegal, adding that “he got really frustrated when we’d have those conversations.”

Trump hosted Brunson in the Oval Office in October 2018 when the American returned to the U.S. after almost two years in a Turkish prison. The pair will be together again on Saturday, when Trump attends the “Value Voters Summit” in Washington for a dinner in Brunson’s honor.

--With assistance from Jennifer Jacobs.

To contact the reporter on this story: Nick Wadhams in Washington at nwadhams@bloomberg.net

To contact the editors responsible for this story: Kevin Whitelaw at kwhitelaw@bloomberg.net, ;Bill Faries at wfaries@bloomberg.net, Ros Krasny

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