The US has slapped sanctions on 21 Iranian-backed firms, increasing pressure over Tehran's controversial nuclear programme and its alleged support for radical groups like Hezbollah and Hamas. Announcing this, the Treasury Department claimed that Iran is the primary founder of Hezbollah and has long been recognised as the most active state sponsor of terrorism. It said these designations expose Iran's use of its state apparatus and state-run social service organisations to support terrorism under the guise of providing reconstruction and economic development assistance or social services. State Department spokesman P J Crowley said the US believes that sanctions is having an effect on the ground in Iran. He said, US feels there may well be a willingness onthe part of Iran to enter into the kind of dialogue that have long been sought. Crowley said, the steps taken, both at the United Nations and now follow-on steps by the United States, by the European Union, and other countries are getting Iran’s attention. He said, the US is making sure that the impact of the sanctions is not felt on the people of Iran.