Iran says it has ended all voluntary cooperation with the International Atomic Energy Agency, after the agency voted to report Tehran's disputed nuclear program to the U.N. Security Council.

Iranian Foreign Minister Manouchehr Mottaki told a news conference Sunday, Tehran has stopped all voluntary measures undertaken in the past several years. He says Iran will continue to honor its commitments to the Nuclear Non-Proliferation Treaty.

Earlier, a Foreign Ministry spokesman said the government was still open to negotiations despite Saturday's vote by the IAEA's board of governors.

Iranian officials also say they will go ahead with planned talks with Russia about the enrichment of uranium

President Bush said the IAEA's decision sends a clear message that the world will not permit Iran to have nuclear weapons.

In Germany Sunday, Russian Defense Minister Sergei Ivanov said he doubted whether sanctions would be effective against Iran.

Some information for this report was provided by AFP, AP and Reuters.