The United States has imposed economic sanctions on nine targets, including six people and three companies, accused of violating anti-Iran sanctions, Press TV reported.
The Treasury Department said in a statement on Tuesday that two Tehran-based tech firms and a United Arab Emirates-based trading company were sanctioned for allegations of helping Iran obtain hundreds of millions of dollars in violation of Washington's sanctions against Tehran.
Six citizens from Iran, Afghanistan, and Saint Kitts and Nevis are also the targets for penalties.
"Although we do not support the imposition of any new nuclear-related sanctions while negotiations are ongoing... we have made clear, by word and deed, that we will continue to enforce our existing sanctions," said David Cohen, Treasury Undersecretary for Terrorism and Financial Intelligence.
Iran is discussing a final deal with six world powers over its nuclear energy program.
Iran's Foreign Minister Mohammad Javad Zarif has already emphasized that the removal of all sanctions should be a main component of the final nuclear deal.
More than a year ago, Iran agreed to an interim deal to suspend 20-percent uranium enrichment in exchange for the lifting of economic sanctions pending on a long-term deal.
Despite progress in the talks, Iran and the five permanent members of the United Nations Security Council - China, Russia, Britain, France, and the United States - plus Germany failed to clinch a final deal by a Nov. 24 deadline. The talks have now been extended until July 1, 2015.