Iran on Friday denied accusations by France, Britain and the United States that its banks were involved in illegal nuclear activity and in financing terrorism. The UN Security Council has imposed three sets of limited sanctions against Iran for refusing to halt uranium enrichment, including a round in March that introduced financial monitoring of Bank Melli and Bank Saderat. Iran has refused to comply with repeated international demands to halt nuclear enrichment, a process that can be used to produce fuel for nuclear weapons or nuclear energy. The US suspects the program is aimed at making nuclear weapons, but Iran maintains it is for peaceful purposes. Earlier this month, Britain, France and the US argued in a letter to the UN Security Council that Iranian banks were trying to get around sanctions by covertly conducting transactions. Iran rejected the charge in a letter to the Council on Friday, saying Iranian banks "have never been involved in any illicit activities . . . because there no such non-peaceful nuclear activities in Iran."