The Pentagon has notified Congress that it plans to transfer about a dozen Guantanamo Bay inmates to at least two countries as part of President Obama's strategy to close the Cuban-based detention center.

A U.S. official told a source late Wednesday the first of the transfers is expected to take place over the next few days with others coming in the next few weeks.

There are 91 enemy combatants currently being held at Guantanamo. The White House has proposed moving 35 of the inmates to other countries and prosecuting the remainder. Those who are ineligible for either solution would remain in U.S. custody.

The Obama administration has said closing the prison would save the U.S. approximately $65 million to $85 million per year, eventually.