The White House has vowed that President Barack Obama will veto any legislation imposing new U.S. sanctions on Iran.
The threat was issued December 19 after 26 senators – or more than one-quarter of the Senate – introduced new Iranian sanctions legislation.
The measure, backed by 13 Republicans and 13 lawmakers from Obama's Democratic Party, would impose sanctions if the Islamic republic violates the interim nuclear agreement with world powers reached in November, or if no final long-term deal is reached to curb Iranian nuclear activities.
Entitled the “Nuclear Weapon Free Iran Act,” the proposed law would seek to further restrict Iranian oil exports and target Iranian mining, engineering, and construction industries.
It was not immediately clear when, or if, the measure will come to a vote in Congress. Lawmakers are due to begin a holiday recess this week until early 2014, and new Iranian sanctions are opposed by the Obama administration and many in Congress.
White House spokesman Jay Carney called the bill unnecessary and possibly harmful, saying it could undermine negotiations currently under way with Iran.
Carney added that Washington could impose new sanctions quickly if the international negotiations with Iran collapse. The spokesman said most Americans support the current effort to reach a diplomatic settlement with Tehran over the Iranian nuclear program.
The Senate legislation was introduced as experts from Iran and the six world powers resumed nuclear talks in Geneva.
In these discussions, experts are trying to determine the details of lifting sanctions against Iran, and what specifically Iran must do to demonstrate it is suspending parts of its nuclear program.
Under the November agreement, Iran stands to receive billions of dollars worth of relief from Western economic sanctions. The sanctions are seen has having crippled the Iranian economy, impacting millions of ordinary Iranians, and forcing the reduction of Iranian oil exports, a key revenue source.
In return for the sanctions relief, Iran has agreed to curb some nuclear work, including limiting uranium enrichment to five percent purity -- well below the threshold needed to make a nuclear weapon -- and to "neutralize" stockpiles of uranium that have been enriched to 20 percent purity, or close to weapons-grade.
The agreement has been given a time-frame of six months to allow negotiators to craft a more permanent settlement.
Iran denies any effort to make a nuclear bomb, saying its atomic program is for power production and civilian uses only.
Earlier this month, Iran halted the international talks after the United States blacklisted a further 19 companies and individuals under existing sanctions. Tehran said the move was against the spirit of the interim deal.
However, progress was reported during a December 9-12 meeting in Vienna between Iran and representatives of the six powers -- the United States, Russia, China, Britain, France, and Germany.
With reports from Reuters, AP and AFP