The United States will seek a gradual move towards sanctions on Iran by the UN Security Council, Nicholas Burns, the undersecretary of state for political affairs said on Wednesday.

"If Iran doesn't respond to words, we believe the world community should entertain the possibility of sanctions," Burns told the House Committee of International Relations.

"But it's going to be incumbent upon our allies around the world to show that they are willing to act," Burns said.

Burns said that the UN Security Council could start debating Iran's nuclear program as early as next week. "We will therefore start a new phase of diplomacy -- action by the UN Security Council starting next week," he said.

Burns also accused Iran of failing to meet the demands of the International Atomic Energy Agency (IAEA) on suspending its uranium enrichment and cooperating with IAEA inspectors.

The United States has accused Iran of trying to develop nuclear weapons under the cover of civilian nuclear programs. However, Iran has said its nuclear programs are for civil purposes only.

The United States has insisted on referring Iran's nuclear issue to the UN Security Council for possible sanctions.

Source: Xinhua