The U.S. Congress on Wednesday passed additional sanctions seeking to further stifleIran's oil exports, just one day after PresidentBarack Obamaannounced new measures to pressure the Islamic republic over its controversial nuclear program.

The House of Representatives voted 421-6 for the new penalties, while the Senate passed them unanimously later. The legislation will land on Obama's desk for his signature.

House Foreign Affairs Committee chairwoman Ileana Ros-Lehtinen said the new sanctions, the toughest ever imposed on Iran, seek to "tighten the chokehold on the regime beyond anything that has been done before."

She told the House that the measures will ultimately deprive Iran of "hard currency and funds needed to sustain its nuclear program." Oil export is the lifeline of the republic's economy.

The new measures, among others, target any individual or entity that works with Iran's petroleum or natural gas sector, engages in mining of uranium with the country, sells oil tankers to Tehran, or provides insurance to the National Iranian Tanker Co.

The move builds on an act signed by Obama late last year that targets financial institutions of foreign countries that purchase Iranian oil.

In his latest efforts to rev up pressure on Iran, which the West suspects is seeking to build nuclear weapons under the cover of its nuclear program, Obama on Tuesday announced additional sanctions against the country's energy and petrochemical sectors.

He also said sanctions were imposed on Bank of Kunlun in China and Elaf Islamic Bank inIraq, alleging that they "have facilitated transactions worth millions of dollars on behalf of Iranian banks that are subject to sanctions for their links to Iran's illicit proliferation activities."

The move sparked strong protest from China, which on Wednesday urged theUnited Statesto cancel its sanctions on Bank of Kunlun and stop damaging ties between the two nations.

"The U.S. side imposing sanctions, in accordance with its domestic law, on a Chinese financial institution has severely violated the principles of international relations and impaired the interests of the Chinese side," Chinese Foreign Ministry spokesman Qin Gang said, voicing "strong dissatisfaction" and "resolute opposition" to the U.S. move.

Iran has insisted on the peaceful nature of its nuclear program, and held three rounds of talks with the United States, Britain,France,Russia, China andGermanyover its uranium enrichment program since mid-April.

Israeli Prime Minister Benjamin Netanyahu, who has threatened preemptive strikes on Iran's nuclear facilities, said on Sunday in Jerusalem that the sanctions had not set back Iran's nuclear program "one iota."

Netanyahu made the comment in his meeting withMitt Romney, the Republican presidential candidate set to face Obama in the November election.

The Obama administration has adopted a sanctions-plus-diplomacy approach to Iran's nuclear problem, and called for time for it to work out.