By Timothy Gardner and Jonathan Saul
WASHINGTON (Reuters) - As Iran's oil exports rise despite U.S. sanctions over its nuclear program, senators from both parties urged President Joe Biden to enable a federal government agency to seize Iranian oil and gas shipments.
Senators Joni Ernst, a Republican, and Richard Blumenthal, a Democrat, said in a letter to Biden that the Department of Homeland Security's Homeland Security Investigations (HSI) office has not been able to seize an Iranian oil shipment for more than a year.
HSI's enforcement has been curtailed by policy limitations within the Department of Treasury's Executive Office for Asset Forfeiture, the senators said in the letter, a copy of which was reviewed by Reuters.
The White House did not immediately respond to a request for comment.
Since the activation of HSI's enforcement program in 2019, it has seized nearly $228 million in Iranian crude and fuel oil linked to Iran's Quds Force, the foreign espionage and paramilitary arm of the Islamic Revolutionary Guards Corps (IRGC), the senators said.
Iran says its nuclear program is for civilian purposes while the United States suspects Tehran wants to develop a nuclear bomb by enriching uranium.
Iran's mission to United Nations did not immediately respond to a request for comment on Thursday.
Iran's oil exports have reached their highest level since the reimposition of U.S. sanctions in 2018, Iranian oil minister Javad Owji said last month. He said that 83 million more oil barrels were exported in the last year than the previous year.
The letter, signed by 12 senators, was sent on the same day that the U.S. Navy said Iran seized a Marshall Islands-flagged tanker in the Gulf of Oman, the latest in a series of seizures or attacks on commercial vessels. Iran's army said it had seized the tanker after it had collided with an Iranian boat.
"While Iran is seizing ships, our own program is completely languishing," an aide to Ernst told Reuters.
The senators asked Biden to direct the Treasury department to ensure that HSI Iranian oil seizures are supported and funded for the remainder of this fiscal year and to explain why there's no funding available for seizures for what they claimed were credible leads related to enforcing Iranian sanctions.
Last year the U.S. tried to confiscate a cargo of Iranian oil around Greece, which prompted Tehran to seize two Greek tankers in the Gulf. Greece’s supreme court ruled that the cargo should be returned to Iran. The two Greek tankers were later released.