WASHINGTON Jan 16 (Reuters) - The U.S. Treasury Department said on Thursday it would allow for a 90-day period to wind down transactions in certain sectors of Iran's economy hit with fresh U.S. sanctions last week.

The period will allow people to wind down transactions in the construction, mining, manufacturing or textiles sectors of Iran's economy that could fall under the sanctions, though new business would still be sanctionable, according to the Treasury Department's website. (Reporting by Daphne Psaledakis Editing by Chizu Nomiyama)