U.S. Secretary of State Hillary Clinton says the United States believes Iran is becoming a military dictatorship, adding that Iran's elite military force, the Revolutionary Guard, is "in effect, supplanting the government."
Clinton made the comments in Qatar Monday before traveling to Saudi Arabia as part of her Gulf region tour to promote efforts to increase pressure against Iran for its nuclear program.
Clinton is meeting with Saudi King Abdullah as well as Foreign Minister Prince Saud al-Faisal to rally Arab support for new sanctions on Iran.
On Sunday at the U.S.-Islamic World Forum in Qatar, Clinton said Washington wants a peaceful solution to the nuclear controversy with Iran, but will not engage the Iranians while they are - in her words - "building their bomb."
The diplomat is also expected to discuss U.S. attempts to renew peace talks between Israelis and Palestinians.
Last year, King Abdullah rebuffed U.S. attempts to seek "confidence building" gestures from Arab nations toward Israel.
Clinton also spoke about the Israeli-Palestinian peace talks Monday in Qatar, saying she is hopeful "serious negotiations" between the two sides will begin this year.
Clinton stressed the Obama administration's commitment to a two-state solution to the Israeli-Palestinian conflict. She also acknowledged frustration over the lack of progress with efforts by U.S. envoy George Mitchell to restart negotiations.
Saudi King Abdullah was the key sponsor of a 2003 Arab League peace initiative that would give Israel full relations with Arab states in exchange for progress made with the Palestinians.
Before leaving Qatar, Clinton said Iran leaves the international community little choice but to impose greater costs for its "provocative steps."
The United States has been pressing the U.N. Security Council to impose a fourth set of sanctions on Iran, which has refused to stop enriching uranium.
Uranium enrichment is a process that can be used to make nuclear weapons. Iran says its atomic program is for peaceful purposes.