The US is likely to announce on Friday that it will give at least seven economies including India, South Korea and Turkey another six-month reprieve from financial sanctions against Iran, two US government sources said.

As Washington works with the economies to rein in Tehran's nuclear ambitions, the State Department will likely extend the waivers, known as "exceptions," because they reduced their purchases of Iran's crude.

The first round of reprieves to the sanctions law signed a year ago came in June.

The sanctions aim to choke funding to Tehran's nuclear program by slashing Iran's oil exports. The West suspects Iran's nuclear program is enriching uranium to levels that could be used in weapons. Tehran says the program is for electricity generation and medical purposes.

U.S. waivers for both China, Iran's top oil consumer, and Singapore expire later, on Dec. 25 - 180 days after they got the first round on June 28.

But one of the government sources and an industry source said those exceptions could also come as soon as Friday.

"There's nothing in the sanctions law that says the U.S. has to wait a full 180 days to announce exceptions for China," the government source said. – Reuters