Companies should “hold off” doing business in Iran because many of the sanctions against the country are still in place despite an interim nuclear deal, the top U.S. Treasury official warned Monday.

Speaking in Turkey, which is looking to expand business opportunities with its neighbor Iran, David Cohen, the U.S. secretary for terrorism and financial intelligence, said a significant portion of sanctions against Iran remained, including in the banking, energy and shipping sanctions.

“Iran is not open for business,” Cohen said. “Businesses interested in engaging in Iran really should hold off. The day may come when Iran is open for business, but the day is not today.”

Last week, the United States and the European Union partially lifted economic sanctions on Iran after it unplugged banks of centrifuges involved in its most sensitive uranium enrichment work. The move was part of a deal aimed at easing concerns over Iran’s nuclear program.

Turkey has expressed hopes that the easing of sanctions against Iran will open business opportunities, especially in the energy sector. Turkish Prime Minister Recep Tayyip Erdogan travels to Iran on Tuesday.

Turkey imports gas and oil from Iran but the Turkish oil refiner, Tupras, was forced to reduce its Iranian oil purchases due to the sanctions.

“What we are working toward is the possibility of a long-term, comprehensive resolution with the Iranians in which they demonstrate that their nuclear program is exclusively for peaceful purposes,” Cohen said.

Cohen also said he expects Turkey’s state-run banking institution, Halkbank, to continue processing oil payments to Iran.

The bank’s head was arrested last month on bribery charges, along with two former Cabinet ministers’ sons, and police seized $4 million in cash in shoe boxes from the bank chief’s home.

(AP)