Iran has dismissed the new U.S. sanctions on Tehran, with the Foreign Ministry spokesman saying Tuesday they are part of a "psychological war" meant to sow discontent among Iranians and insisting the measures would not halt the country's nuclear program.

Washington ordered the new penalties on Monday, giving U.S. banks additional powers to freeze assets linked to the Iranian government and close loopholes that officials say Iran has used to move money despite earlier restrictions imposed by the U.S. and Europe.

The United States and its allies suspect Iran's nuclear activities are geared toward producing an atomic weapon. Iran denies the charge, insisting its controversial uranium enrichment program is only for peaceful purposes, such as power production.

Ramin Mehmanparast, the foreign ministry spokesman, said Iran's central bank has no financial transactions with the United States and would not be affected by the measures.

He told reporters in Tehran on Tuesday that the penalties are just "propaganda."

"Many of these (U.S.) activities are in the sphere of psychological war and propaganda, and they cannot affect our work," he said.

"When they impose sanctions on our central bank even though we have no transactions with them, it shows ... they think they are able to put pressure on our people. create concerns and social discontent," he added.

The new, stricter sanctions, authorized in legislation that President Barack Obama signed in December, will be enforced under an order he signed Sunday. The measures target Iran's Central Bank and its other financial institutions, intended to complicate the country's ability to conduct international commerce.

The U.S. and Europe want to deprive Iran of the oil income it needs to run its government and pay for the nuclear program. But many experts believe Iran will be able to find other buyers outside Europe.

Mehmanparast insisted the penalties will have no effect and would not halt Iran's nuclear program.

"When you apply the highest level of your power to impose sanctions on a nation and that nation continues on its path decisively, it proves you do not have enough power to halt it," he said, addressing the U.S.

"These measures will not have enough impact on Iran," Mehmanparast said. "These miscalculations will bear no fruit for the U.S. and Western countries."