Iranian legislators instructed the government yesterday to develop a nuclear fuel cycle that would include resuming the process of enriching uranium.
That prospect that has drawn criticism from the United States and Europe because it could be used in developing atomic weapons.
The vote came as a spokesman for Iran's foreign ministry said it was giving Europe a "last chance" in nuclear talks.
Iran suspended enrichment of uranium six months ago under international pressure led by the United States, which accuses Tehran of trying to make nuclear weapons. Iran maintains its program is peaceful and only aimed at generating electricity.
The European Union has threatened to take Iran to the UN Security Council for possible sanctions if it again starts uranium reprocessing. Enriched uranium is useful in the generation of electricity, which is permitted under the Nuclear Non-Proliferation Treaty, but it also can be turned into nuclear weapons.
The bill approved Sunday by 188 of the 205 deputies attending the parliamentary session doesn't force the government to immediately resume uranium enrichment but pressures it not to give up its nuclear program, including uranium enrichment.
The legislation was viewed as strengthening the government's hand in negotiations with European Union representatives, allowing it to demonstrate domestic pressure to pursue its nuclear programme as talks have deadlocked.
The Guardian Council, a hard-line body vetting legislation, is widely expected to approve the legislation, making it law.
AP