In a letter that also went to U.N. Secretary-General Ban Ki-Moon, Iran singled out the United States and its allies for their pursuit of the sanctions, Iran's Fars News Agency said.

The letter accompanied an Iranian proposal for "constructive negotiations" and proposed solutions for a number of issues.

Iran said it "believes that there is an extensive range of security issues, regional and international developments, nuclear energy, terrorism, democracy, etc., that provide a substantive potential for cooperation."

A copy was passed along to Javier Solana, the chief EU foreign policy official. He said he would share its contents with Germany, France and Britain.