The United States has expressed its concerns with India about its reported opposition to refer Iran's nuclear issue to the United Nations Security Council, a senior US State Department official said Thursday.

"We have registered our concerns with the Indian government of course," US Under Secretary of State for Political Affairs Nicholas Burns said at a Congressional hearing.

US Secretary of State Condoleezza Rice will also raise the issue in meetings with her Indian counterpart Natwar Singh and Prime Minister Manmohan Singh during the UN General Assembly next week, Burns said.

According to media reports, Singh, at a meeting with Iranian President Mahmood Ahmadinejad earlier this week, said that New Delhi was opposed to referring Iran's nuclear issue to the UN Security Council.

The United States has accused Iran of undergoing a secret nuclear program and has threatened to refer the issue to the UN Security Council for possible sanctions.

Source: Xinhua