Two ex-Guantanamo Bay detainees transferred to Ghana by the United States have been granted refugee status and now cannot be deported even though the contractual period they must stay has elapsed, the government said on Wednesday.

The Yemeni nationals were sent to Ghana in January 2016 for an initial two-year period after spending more than a decade at the U.S.-operated Guantanamo Bay prison for suspected terrorism.

The opposition is concerned that now the two years has expired, the United States no longer has shared responsibility for making sure the suspects pose no danger and has been pressing the government to deport them.

Their arrival in Ghana has long been disputed. President Nana Akufo-Addo, who was the main opposition leader at the time of the transfer, criticised the government for accepting the two Yemenis at the time.

Now his government is coming under pressure.

“The government is constrained from immediately deporting them except to explore mutually acceptable means with other countries and the refugees,” Foreign Minister Shirley Ayorkor Botchwey told Reuters. “If we don’t get them to consent we cannot send them packing.”

Mahmud Umar Muhammad Bin Atef and Khalid Muhammad Salih al-Dhuby have lived in the capital, Accra, since they arrived. Neither man was tried or convicted at Guantanamo, nor have they been accused of any crime since arriving in Ghana.