NEW YORK (Reuters) - A U.S. judge on Wednesday refused to overturn the conviction of a Mehmet Hakan Atilla, an executive at Turkey’s majority state-owned Halkbank, on charges that he helped Iran evade U.S. sanctions.

U.S. District Judge Richard Berman in Manhattan said the evidence against Atilla was “clearly sufficient” to support the Jan. 3 verdict. He said he could only overturn that verdict if the evidence were “nonexistent or so meager that no reasonable jury could find guilt beyond a reasonable doubt.”

Victor Rocco, a lawyer for Atilla, declined to comment. Atilla, who was convicted of five counts including bank fraud and conspiracy to violate U.S. sanctions law, is scheduled to be sentenced by Berman on April 11.

Atilla’s lawyers had moved for Berman to enter a verdict of not guilty during the trial, after the prosecutors finished presenting their evidence. Berman’s ruling on Wednesday denied that motion.

Much of the testimony against Atilla during his four-week trial came from Reza Zarrab, a Turkish-Iranian gold trader who pleaded guilty to U.S. charges and agreed to cooperate with prosecutors.

Zarrab told jurors that he masterminded a scheme to allow Iran to spend the proceeds of its oil and gas revenues abroad using fraudulent gold and food transactions through Halkbank, violating U.S. sanctions. He said Atilla helped design some of the transactions.

Atilla, testifying in his own defense at the trial, denied the accusations.

The case strained relations between the United States and Turkey, which are NATO allies, as Zarrab testified that he paid bribes to Turkish officials and that Turkish President Tayyip Erdogan, then prime minister, personally signed off on parts of the scheme.

Erdogan denounced the verdict at a Jan. 5 news conference.

“If this is the U.S. understanding of justice, then the world is doomed,” Erdogan told a news conference before his departure to France for an official visit.

The U.S. trial carried echoes of an investigation in Turkey in 2012 and 2013 that involved Zarrab and multiple government officials. One of the prosecutors’ witnesses was a former Turkish police officer, Huseyin Korkmaz, who said he led that investigation.

The Turkish government has said that followers of the U.S.-based cleric Fethullah Gulen were behind both the Turkish investigation and the U.S. case, as well as the 2016 failed coup in Turkey. Gulen has denied the accusations.