The International Atomic Energy Agency says Iran has carried out tests that are "relevant to the development of a nuclear explosive device." (Creative Commons)

"In the past five years, we have reduced... the amount of oil imported [from Iran]," said Japanese Finance Minister Jun Azumi during a joint press conference with US Treasury Secretary Timothy Geithner. "We wish to take planned and concrete steps to further reduce this share, which now stands at 10 percent."

Iran is a major oil supplier to Japan, along with Saudi Arabia and the United Arab Emirates. According to the BBC, Japan is urging Gulf Arab nations to boost oil exports in order to make up shortages.

Geithner praised the Japanese support for sanctions over Iran's nuclear program, which critics say is aimed toward the development of atomic bombs. 

"We very much appreciate the support Japan has provided standing with us and the international community in support of this very important strategic objective," said Geithner, stressing that the U.S. is working closely with Euope and other allies to “substantially increase the amount of pressure” against the Iranian regime.

China, meanwhile, has called for cooperation between Iran and the International Atomic Energy Agency.

"To place one country's domestic law above international law and press others to obey is not reasonable," Liu Weimin, a Chinese ministry spokesman told reporters Wednesday.

Last Wednesday the European Union, in a bold move, announced a plan to ban Iranian oil imports, a move that experts say will further undermine the Iranian regime’s hold on power.

"The tide has truly turned over the past few months as evidenced by the U.S.'s move to sanction Iran's Central Bank, Chinese companies leaving Iran, and Europe's impending embargo of Iranian oil imports," said Ambassador Mark D. Wallace who heads United Against a Nuclear Iran, a non-partisan coalition, in a statement. "Just months ago these measures were being described as unlikely, yet intense public pressure, Iranian intransigence, and committed lawmakers have made them a reality."

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