Iran is in clear violation of a treaty designed to prevent the spread of nuclear weapons, US Secretary of State Hillary Rodham Clinton said Sunday.

The UN is holding a conference this coming week on the Nuclear Non-Proliferation Treaty and Iran's president, Mahmoud Ahmadinejad, is expected to address delegates ahead of Clinton on Monday.

Clinton told NBC's "Meet the Press" that Ahmadinejad's trip is an effort to divert attention and confuse people about Iran's violation of the treaty.

She said that the UN conference was designed to make clear the global commitment to disarmament, peaceful nuclear energy and limiting the spread of nuclear weapons.

US Jewish groups, gearing up for the Iranian leader’s visit to New York, have recently voiced loud opposition to Ahmadinejad’s participation in the NPT conference. The Conference of Presidents of Major American Jewish Organizations contacted ambassadors of UN member states, and placed newspaper ads to appear on Monday, urging diplomats to walk out with he speaks on Monday morning.