In a press conference, Iranian government spokesman Gholam Hossein Elham told media that Tehran would "use its capability to decide whether to stay within the treaty or to quit it if our rights are deprived or under pressure".

"......The parliament's approval (for the bill) does not necessarily mean quitting the NPT... and we want to act within the framework of the treaties that we have accepted in a transparent way but being part of a treaty is a neutral thing based on duties and rights," he added.

Referring to the possible revision of Iran's relations with the International Atomic Energy Agency (IAEA), Elham said his government would decide it based on the attitude taken by the international community over the controversial nuclear program.

Iran's parliament last Wednesday passed a bill urging the government to reduce its cooperation with the UN nuclear watchdog IAEA, in a reaction to the UN sanctions imposed on Tehran, the state radio reported.

The bill was approved by the powerful Guardian Council immediately and formally became a law, but it will be effective in 15 days after President Mahmoud Ahmadinejad affirms it.

It's not clear if the Iranian government has changed its stance, because Iran's Deputy Foreign Minister Mehdi Mostafavi has said that "Iran had no intention to retreat from the NPT" after the UN Security Council decided to impose sanction against Tehran's nuclear program.

The UN Security Council Resolution 1737, adopted unanimously on Saturday, demanded that Iran "suspend all enrichment-related and reprocessing activities, including research and development, and work on all heavy water-related projects."

The resolution also called on all states to impose a ban on trade with Iran in goods related to its nuclear programs and ballistic missile delivery systems.

It demanded that "all states shall freeze the funds, other financial assets and economic resources" owned or controlled by officials and companies in the country's nuclear and missile programs.

Shortly after the UN Security Council voted unanimously for the resolution, the Iranian Foreign Ministry issued a statement lashing out at the resolution as an "illegal measure."