TEHRAN - Iran on Tuesday rejected as an "antagonistic move" a tightening of US sanctions that targets the Islamic state's central bank and gives US banks new powers to freeze assets linked to the Iranian government."It is an antagonistic move ... a psychological war which has no impact ... There is nothing new, it has been going on for over 30 years," Foreign Ministry spokesman Ramin Mehmanparast told a weekly news conference. "Sanctions will not have any impact on our nuclear course."The move, in an executive order signed by President Barack Obama, was the latest measure to target the Central Bank of Iran, and was intended to close loopholes in existing sanctions Tehran has faced.In a letter to Congress, Obama said Iranian banks were hiding transactions to undercut the financial sanctions the United States and other powers have imposed in response to Iran's nuclear program, which the West says is aimed at building bombs.Iran says it needs nuclear technology to generate electricity and not to build bombs.