By Patricia Zengerle
WASHINGTON (Reuters) - Forty-nine of the 50 Republican U.S. senators said on Monday they will not support an emerging new nuclear deal between Iran and world powers, underscoring their party's opposition to attempts to revive a 2015 accord amid fears talks might collapse.
Citing press reports about the as-yet-unfinalized agreement, which could be torpedoed by Russian opposition, the lawmakers said in a statement that Democratic President Joe Biden's administration might reach a deal to weaken sanctions and lessen restrictions on Iran's nuclear program.
They pledged to do everything in their power to reverse a an agreement that does not "completely block" Iran's ability to develop a nuclear weapon, constrain its ballistic missile program and "confront Iran's support for terrorism." Tehran denies it has ever sought atomic bombs.
No congressional Republicans backed the 2015 agreement between Tehran and major powers, reached under Democratic President Barack Obama. A handful of Democrats also objected.
Congress may have the right to renew an agreement under the 2015 Iran Nuclear Agreement Review Act (INARA), but they are unlikely to be able to kill a deal after failing to do so seven years ago, when Republicans controlled Congress.
Democrats now hold slim majorities in both the House of Representatives and Senate.
The accord eased sanctions in return for limits on Iran's enrichment of uranium, making it harder for Tehran to develop material for nuclear weapons. It fell apart after Republican President Donald Trump withdrew the United States in 2018.
Talks resumed after Biden became president last year.
Attempts to clinch a new deal were left in limbo after a last-minute demand by Russia - at odds with the West over its invasion of Ukraine - forced the powers to pause talks in Vienna despite having a largely completed text.
A spokesperson for Iran's foreign ministry said on Monday that Washington needed to make a decision to wrap up a deal.
(Reporting by Patricia Zengerle; editing by Grant McCool)
