Washington, Apr 14 (DPA): US President Barack Obama has said Iran must face "consequences" for failing to assure the world of the nature of its nuclear programme and called on countries to back sanctions against the Islamic state.

"I want to see us move forward boldly and quickly, to send the kind of message that will allow Iran to make a different calculation," Obama said Tuesday after wrapping up a two-day summit on nuclear security.

Obama said the failure to confront Iran will undermine efforts to enforce the nuclear Non-Proliferation Treaty (NPT).

"There have to be some consequences," he said. "And if we are saying that the NPT is important, if we're saying that non-proliferation is important, then when those obligations are repeatedly flouted ... it's important for the international community to come together."

Obama has said he hopes to submit a new sanctions resolution to the UN Security Council this spring and get a successful vote. On the sidelines of the summit, he has been holding meetings with key leaders to get their support, including Chinese President Hu Jintao.

US officials say Hu agreed to cooperate with the United States on drafting a resolution, but it remained unclear if Beijing would back the tough measure sought by Washington.

Iran rejects US and Western allegations that it is developing a nuclear weapons capability, saying its nuclear work is limited to meeting energy needs.