The Reuters news agency is reporting that Republican leaders of the U.S. House plan to vote after the November 8 elections on reauthorizing the Iran Sanctions Act, setting up a potential showdown with the White House.
The law, which authorizes sanctions over Iran's nuclear program and ballistic missile tests, expires on December 31.
Representative Ed Royce, chairman of the House Foreign Affairs Committee, is expected to introduce a "clean" 10-year renewal, which aides said was likely to pass the House.
Its fate in the Senate is uncertain, however, and it may be opposed by the White House.
The Obama administration has asked Congress to hold off on renewing the law, saying it has enough power even if it expires to reimpose economic sanctions on Iran if Tehran violates its nuclear agreement with world powers.
"The president and the Treasury Department retain significant sanctions authority that already has been used to impose costs on Iran for their flagrant violation of their international obligations," White House spokesman Josh Earnest said on October 25.