Low oil adds to Iran woes during nuclear pact: U.S. official

(Reuters) - The swoon in oil prices means Iran will lose billions of dollars more in revenue during the seven-month extension of its temporary nuclear agreement, a U.S. Treasury Department official specializing in terrorism and financial intelligence said on Wednesday.

"If oil prices remain at current levels, Iran will lose an additional $11 billion in oil revenue from what it was expecting to take in during this most recent seven-month extension" of the temporary pact, David Cohen, the U.S. undersecretary for terrorism and financial intelligence said in prepared remarks for a Senate Foreign Relations Committee hearing.

Brent oil prices have fallen by more than half since the summer to just above $49 a barrel.

The United States, Britain, France, Germany, Russia and China are in talks with Iran to forge a deal over the country's nuclear program, which Tehran says is purely for peaceful purposes. They failed to meet a deadline for a deal in November and extended the talks until mid-2015.

As the talks drag, Republican and Democratic lawmakers are moving forward with a new sanctions bill.

Cohen urged lawmakers not to pass more sanctions legislation now. Even if implementation of new sanctions were delayed, "would more likely hinder, rather than advance, the prospects for a diplomatic solution that verifiably prevents Iran from obtaining a nuclear weapon," he said.