The U.S. House of Representatives unanimously passed legislation on Thursday that seeks to bar Iran's proposed UN ambassador, Hamid Abutalebi, from entering the United States, three days after its approval by the Senate.
The legislation, which needs President Barack Obama's signature to become law, would deny admission of anyone as a representative to the United Nations who has engaged in terrorist activity against the United States.
The White House has not said whether Obama will sign the bill. Two U.S. officials told Reuters on Wednesday that a decision by the administration on whether to bar Abutalebi was imminent.
"We've made clear and have communicated to the Iranians that the selection they've put forward is not viable, and we're continuing to make that understood," White House spokesman Jay Carney told reporters on Air Force One.
The U.S. government objects to Abutalebi because of his suspected participation in a Muslim student group that held 52 Americans hostage for 444 days starting in 1979, when the group seized the U.S. Embassy in Tehran, the Iranian capital.
Representative Doug Lamborn, the Colorado Republican who sponsored the bill in the House, described Abutalebi as a "terrorist." The Senate bill was sponsored Senator Ted Cruz, a conservative Republican firebrand and central figure in the U.S. government shutdown battle last year.
Barring a proposed envoy to the United Nations would be a rare and potentially precedent-setting move that could test U.S. influence over the world body.
Iran has rejected U.S. reservations about Abutalebi as unacceptable. The veteran diplomat has played down his personal role in the U.S. embassy's takeover, saying he was only a translator.
The controversy does not appear -- so far at least -- to have affected negotiations between major powers and Iran over curbing Iran's nuclear program.