U.S. Secretary of State Colin Powell says the United States does not intend to bring about regime change in Iran, but expressed concern over Tehran's nuclear ambitions and ties to terrorism.

In an interview with CNBC television airing Sunday, Mr. Powell said the United States is not getting ready to invade Iran, and that it was up to the Iranian people to decide their own future.

He did express concern over Iran's nuclear activities and the possibility it could be developing atomic weapons, but said the international community and the United Nations are now taking the matter more seriously.

Mr. Powell's comments came as Iranian and European Union representatives are trying to finalize a deal that would allow Tehran to avoid possible U.N. Security Council sanctions by suspending uranium enrichment activities.