WASHINGTON - The first of 17 detainees scheduled to be released from the Guantanamo Bay prison in January will be transferred next week, as the Obama administration continues to reduce the population at the controversial detention center in Cuba, a senior U.S. official said Monday.

Another three detainees are slated to appear before a review board during January to determine whether they can also be considered eligible for transfer to another country, the official added.

Defense Secretary Ash Carter notified Congress earlier this month that 17 detainees would be transferred to other countries in January. The 17 are more transfers than Carter has approved all year, and they will reduce the total detainees at Guantanamo to 90, with 31 still eligible for transfer.

In the 10 months since Carter took office in February, he transferred 15 detainees out of Guantanamo.

The official spoke on condition of anonymity.

The White House has been struggling to close the Guantanamo Bay detention center, but efforts stalled in recent months amid staunch opposition in Congress to any plan to move detainees to a U.S.-based prison site. The $607 billion defense policy bill passed by Congress in November includes a provision that bans any movement to the United States.

President Obama opposed the provision, but signed the bill.