"Psychological Warfare"
Iranian foreign ministry spokesman Ramin Mehmanparast, quoted by state television, said: "European Union sanctions on Iranian oil is psychological warfare ... Imposing economic sanctions is illogical and unfair but will not stop our nation from obtaining its rights."
Deputy Foreign Minister Abbas Araqchi told the IRNA news agency that the more sanctions were imposed on Tehran "the more obstacles there will be to solve the issue".
"The European countries and those who are under American pressure, should think about their own interests. Any country that deprives itself from Iran's energy market, will soon see that it has been replaced by others," Mehmanparast added.
The EU measures included an immediate ban on all new contracts to import, purchase or transport Iranian crude and petroleum products. However, EU countries with existing contracts to buy oil and petroleum products can honour them up to July 1, and there would be a review of the plans before then.
EU officials said they also agreed to freeze the assets of Iran's central bank and ban trade in gold and other precious metals with the bank and state bodies.
EU foreign policy chief Catherine Ashton said of the new sanctions: "I want the pressure of these sanctions to result in negotiations ... I want to see Iran come back to the table and either pick up all the ideas that we left on the table ... last year ... or to come forward with its own ideas."
Iran has said lately that it is willing to hold talks with Western powers, though there have been mixed signals on whether conditions imposed by either side make new negotiations likely.