"The US and the western countries are unable to resolve the issue of terrorism by continuing their previous policies," Zarif said during a meeting with his Spanish counterpart Jose Manuel Garcia-Margallo in New York on Friday.
He noted that the US cannot fight terrorists and at the same time try to weaken the Syrian government.
The Iranian foreign minister pointed to the US dual-track policy in dealing with terrorism in Syria and Iraq, and said, "The Americans did not take any effective measure against four months of savagery of the Islamic State of Iraq and the Levant (ISIL) terrorists in Iraq like halting their direct and indirect aid to the them."
The Spanish minister, for his part, voiced Madrid's readiness to negotiate with regional courtiers, Iran in particular, to seek a proper solution to the crises in Syria and Iraq.
Garcia-Margallo also invited his Iranian counterpart to pay an official visit to Spain in the near future.
Iran and Spain have enjoyed amicable ties for centuries based on mutual understanding.
The volume of the trade exchanges between the two countries amounted to 4 billion Euros in 2011, while the figure stood at 3.5 billion Euros in 2009. But the United States' unilateral sanctions have decreased the figures in the last two years.
