Obama Sends Plan to Congress to Close Guantanamo Bay Prison

— -- After sending a plan to Congress to close the Guantanamo Bay detention facility this morning, President Obama stressed that the prison "undermines" the country's national security and must be closed.

"This is about closing a chapter in our history. It reflects the lessons we've learned since 9/11," Obama announced as he detailed his proposal from the Roosevelt Room at the White House.

The proposal sets up a final battle with Congress as the president works to move dozens of detainees to the United States before he leaves office next year.

"We recognize that this is going to be a challenge," he said. "We are going to keep making the case to Congress."

The president’s plan has four primary elements, including transferring to other countries detainees who are already designated for transfer. Although 91 detainees are now at Guantanamo, 35 are already eligible for transfer if the administration can find another country to take them. Officials anticipate getting the prison’s population below 60 later this year.

The plan aims at accelerating periodic reviews of authority to detain an individual, prosecuting detainees who are facing charges, and working with Congress to establish a location in the homeland to securely hold detainees who cannot be transferred. Lastly, the president wants to move all remaining detainees to the United States.

"Our preferred option," Obama said, "must be our strong, proven federal courts."

The proposal does not specifically endorse any single facility, but the administration believes moving 30 to 60 detainees would cost between $290 to $475 million, upfront costs it believes would be recovered within years compared to keeping detainees at Guantanamo.

"I am very clear-eyed about the hurdles to finally closing Guantanamo. The politics of this are tough," he said. "If it were easy, it would have happened years ago."