WASHINGTON -- Two Republican lawmakers on Saturday accused President Barack Obama of breaking the law by approving the release of five Afghan detainees held at Guantanamo Bay, Cuba, in exchange for a U.S. soldier believed held by Islamist insurgents for five years.

The White House agreed that actions were taken in spite of legal requirements and cited "unique and exigent circumstances" as justification.

Sgt. Bowe Bergdahl, 28, of Hailey, Idaho, was handed over to U.S. special operations forces by the Taliban. In return, five Afghans who were held at a U.S. detention facility in Cuba were released to the custody of the government of Qatar, which served as a go-between in negotiations for the trade.

Rep. Howard "Buck" McKeon of California and Sen. James Inhofe of Oklahoma said in a statement that Obama is required by law to notify Congress 30 days before any terrorists are transferred from the U.S. facility. They said Obama also is required to explain how the threat posed by such terrorists has been substantially mitigated.

McKeon is chairman of the House Armed Services Committee. Inhofe is the top Republican on the Senate Armed Services Committee.

In response, the White House said it moved as quickly as possible given the opportunity that arose to secure Bergdahl's release. Citing "these unique and exigent circumstances," the White House said a decision was made to go ahead with the transfer despite the legal requirement of 30 days advance notice to Congress.

While saying they celebrate Bergdahl's release, McKeon and Inhofe warned that the exchange "may have consequences for the rest of our forces and all Americans."

"Our terrorist adversaries now have a strong incentive to capture Americans. That incentive will put our forces in Afghanistan and around the world at even greater risk," they said.

Senate Majority Leader Harry Reid, a Nevada Democrat, said in a statement that "the safe return of Sgt. Bowe Bergdahl is an answer to the prayers of the Bergdahl family and a powerful reinforcement of our nation's commitment to leave no service member behind."