The prospects for any transfer of Guantanamo inmates to the US mainland have lessened in recent weeks after the US congress acted to block funding to pay for such moves.
Many of the detainees have already been cleared for release, but US officials are having difficulty finding other countries that will take them.
Three Saudi Guantanamo detainees were transferred to Saudi Arabia "under appropriate security measures" last week, the US justice department said on Friday.
The Saudi transfers followed the transfer of six other detainees last week. Four Chinese Uighurs were released in Bermuda, and one detainee from Iraq and another from Chad were transferred to their home countries.
The Guantanamo camp in southeast Cuba was set up in 2002 to house suspected al-Qaeda and Taliban fighters detained as part of the "war on terror" waged by Obama's predecessor, George Bush.
Since then, more than 540 detainees have been transferred from Guantanamo to at least 30 countries.
Obama has vowed to shut the facility by January 2010 but about 230 detainees remain, many held without charge.