United States Senator John McCain, R-Arizona, called on Washington to strongly support Europe`s ongoing nuclear and political talks with Iran. "The United States needs to vigorously support European leadership on this issue but our friends must also realize that no deal will be worthwhile unless it includes a verifiable monitoring regime," McCain said Saturday evening in his address to the 41st Munich Conference on Security Policy. The EU has vainly called on the US to play a more active role in the sensitive nuclear negotiations with the Islamic Republic of Iran. America has so far ruled out direct political and security talks with Iran.