The U.S. Congress is moving to tighten sanctions on Iran, following last month's revelation of an alleged Iranian plot to assassinate Saudi Arabia's ambassador to Washington.

The House Foreign Affairs Committee on Wednesday approved sweeping legislation that would tighten U.S. sanctions on Iran's financial, petroleum, and nuclear interests.

The measures would deny a U.S. visa to anyone involved with Iran's oil or gas industries. There is an amendment aimed at cutting Iran's central bank off from global financial markets.

The legislation would also attempt to isolate Iran's security forces and boost the organizational and communications abilities of anti-government demonstrators.

Iran denies involvement in any foreign assassination plots.

Last week, U.S. Secretary of State Hillary Clinton said on VOA's Persian News Network that the Iranian Revolutionary Guards Corps is becoming more involved in running Iran and that the country may be heading toward military dictatorship.

She also said the U.S. plans an online embassy and wants to circumvent what she called Iran's “electronic curtain.” Additionally, Clinton said the U.S. does not seek conflict with the Iranian government, but wants to support those in Iran who are seeking democratic reform.