GENEVA- A senior U.S. arms control official said on Tuesday that Iran's missile programme is destabilising the Middle East and increasing the risk of a "regional arms race".

Yleem Poblete, Assistant Secretary of State for Arms Control, Verification and Compliance, told the U.N.-sponsored Conference on Disarmament that Washington would aggressively counter "Iran's regional proliferation of ballistic missiles and its unlawful arms transfers".

She urged "all responsible countries" to enforce United Nations Security Council resolutions restricting the transfer of missile-related technologies to Iran.

(Reporting by Stephanie Nebehay and Babak Dehghanpisheh;) ((Stephanie.Nebehay@thomsonreuters.com; +41 58 306 2161; Reuters Messaging: stephanie.nebehay.thomsonreuters.com@reuters.net; twitter @StephNebehay))