WASHINGTON - The White House apologised for keeping lawmakers in the dark regarding the exchange of an American soldier for five Taliban fighters, senators said Tuesday, as controversy grew over the issue.
Administration officials plan a classified briefing for the full 100-member chamber Wednesday, with lawmakers from both parties fuming over the trade, which saw captured soldier Bowe Bergdahl released Saturday to US special forces in Afghanistan.
Senate Intelligence Committee chair Dianne Feinstein, a senior member of President Barack Obama's Democratic Party, said the White House breached US law when it failed to alert Congress to the proposed trade.
"It comes with some surprise and dismay that the transfers went ahead with no consultation, totally not following the law," she told reporters.
"We're very dismayed about it."
Feinstein reflected mounting bipartisan concern as lawmakers questioned the merits of releasing from Guantanamo five hardened Taliban fighters and officials in exchange for Bergdahl.
Seeking to mop up the political fallout, a senior White House official called Senator Saxby Chambliss, the Intelligence Committee's top Republican, late Monday "apologising for not giving us advance warning," Chambliss said.
Feinstein said she too was called Monday, by National Deputy Security Advisor Tony Blinken, who offered his apology.
Lawmakers have pounced on Obama for not giving Congress 30 days notice before releasing any detainee at the Guantanamo Bay military prison, as required in a law signed in December.
Chambliss and Feinstein pointed to such assurances made in 2012 by then-Secretary of State Hillary Clinton when a similar swap for Bergdahl was mulled.
Senate Democrat Carl Levin said Obama put Congress "on notice" last December in a signing statement saying he has constitutional authority to move quickly on detainees.
And Senate Majority Leader Harry Reid said he was told of the swap Friday and that he supported the exchange.