NEW YORK (Reuters) - Former New York City Mayor Rudolph Giuliani went to Turkey to meet with the country’s president and sought meetings with U.S. government officials in an attempt to end U.S. prosecution of a wealthy Turkish gold trader charged with conspiring to violate U.S. sanctions on Iran, Manhattan federal prosecutors said.

FILE PHOTO: Former New York City Mayor Rudolph Giuliani speaks to members of the news media at Trump Tower in New York, U.S. November 22, 2016. REUTERS/Mike Segar

The moves were disclosed in a letter on Friday to U.S. District Judge Richard Berman, who is overseeing the case in which the trader, Reza Zarrab, is accused of conspiring with others to conduct illegal transactions through U.S. banks on behalf of Iran’s government and other Iranian entities.

The new disclosures highlight the politically charged nature of a case that expanded in scope earlier this week with the arrest in New York of an executive at a Turkish state-owned bank charged with conspiring with Zarrab to evade sanctions.

Zarrab, a dual national of Iran and Turkey, had been arrested in 2013 in a corruption probe of people with close ties to Recep Tayyip Erdogan, who was prime minister of Turkey at the time. Erdogan is currently president.

In the letter prosecutors said Giuliani and former U.S. Attorney General Michael Mukasey - both recently added to Zarrab’s legal team - traveled to Turkey shortly after February 24 to meet with Erdogan to discuss ways to end the prosecution. Giuliani informed the office of Attorney General Jeff Sessions about the planned trip, according to the letter.

Acting U.S. Attorney Joon Kim in Manhattan said that Mukasey and Giuliani, who is a close ally of President Donald Trump, had also sought to meet with other officials in the U.S. government on the issue. “Mr. Giuliani and Mr. Mukasey’s efforts are aimed at reaching a disposition in the case,” Kim wrote in the letter.

Kim has sought to question whether Giuliani and Mukasey should be allowed to represent Zarrab given the potential conflicts of interest. Zarrab allegedly victimized at least eight large banks which are current or former clients of Giuliani and Mukasey’s law firms.

Kim had called earlier this week for a special hearing to make sure Zarrab understands the potential conflict.

Benjamin Brafman, an attorney for Zarrab, responded in a letter to the court on Friday, saying he would consent to a limited hearing but stressed that he believed the prosecution had no right to question the actions of Giuliani and Mukasey.

“That information quite frankly is none of the Government’s business,” Brafman wrote.