Zarrab pleaded guilty in 2017 to conspiring to evade U.S. sanctions, eventually providing testimony that helped convict former Halkbank official Mehmet Hakan Atilla. His cooperation became a centerpiece of a broader federal probe that accused the bank of funneling $20 billion in restricted Iranian oil revenue through complex webs of fake food shipments and gold trades.

While the criminal proceedings against the individual were reaching their conclusion, the corporate case against Halkbank remained a persistent diplomatic friction point between Washington and Ankara. Turkish President Recep Tayyip Erdogan previously condemned the legal action as unlawful. The dispute finally settled last month when Judge Berman dismissed the charges against the bank. This resolution followed a Justice Department agreement requiring Halkbank to appoint a compliance monitor to oversee its future anti-money laundering protocols. The deal, finalized as U.S.-Turkey relations hit a multi-decade high, was reportedly linked to Turkey's diplomatic efforts in securing a 2024 ceasefire between Israel and Hamas.