ISTANBUL (Reuters) - Turkish lender Aktif Bank said on Thursday it had not violated any U.S. or international sanctions, after it was mentioned in the U.S. case regarding Iran sanctions violations.

Turkish gold trader Reza Zarrab, who is a witness, testified on Wednesday that he had initially handled Iranian transactions through Aktif Bank. He said Aktif Bank at first hesitated to open an account for him and it shut down the account after receiving a warning from the United States.

“No transaction violating U.S. or international sanctions has occurred on behalf of our bank,” the lender said in a statement. “We have and continue to cooperate with international and national institutions and the result of this case will not have negative impacts on us.”

Zarrab said he used Halkbank to continue his transactions with Iran after Aktif Bank stopped working with him. A Halkbank executive, Mehmet Hakan Atilla, is a defendant in the case. Atilla has pleaded not guilty.