MIAMI » Six prisoners from Guantanamo Bay have been transferred to Uruguay, the U.S. government said Sunday, announcing a resettlement deal that had been delayed for months by security concerns in the Pentagon and political considerations in the South American country.

The six are the first prisoners transferred to South America from the U.S. base in Cuba, part of a flurry of recent releases amid a renewed push by President Barack Obama to close the prison.

Uruguayan President Jose Mujica agreed to accept the six men — four Syrians, a Tunisian and a Palestinian — as a humanitarian gesture and said they would be given help getting established in a country with a small Muslim population.

All six were detained as suspected militants with ties to al-Qaeda in 2002 but were never charged. They have been cleared for release since at least 2010 but they could not be sent home and have languished as the U.S. struggled to find countries willing to accept them.

"We are very grateful to Uruguay for this important humanitarian action, and to President Mujica for his strong leadership in providing a home for individuals who cannot return to their own countries," U.S. State Department envoy Clifford Sloan said.

Mujica had agreed to take the men in January. Obama administration officials have been frustrated that the transfer took so long and blame outgoing Defense Secretary Chuck Hagel for not approving the move sooner. They said the deal sat for months on Hagel’s desk, awaiting his signature as required by law, but the Pentagon didn’t send the notification of the transfer to Congress until July.

By then, the transfer had become an issue in Uruguay’s political election and Uruguayan officials decided to postpone it until after the Oct. 26 vote. Tabare Vazquez, a member of Mujica’s ruling coalition and a former president, won a runoff election on Nov. 30.

The men’s release brings the total number of prisoners at Guantanamo to 136 — the lowest number since the first month the prison opened in January 2002.

Obama pledged to close the prison upon taking office but was blocked by Congress, which banned sending prisoners to the U.S. for any reason, including trial, and placed restrictions on sending them abroad.

The restrictions on sending them overseas have been eased and the U.S. has released 19 prisoners so far this year. Officials say several more are expected by the end of the year.

Prisoners have been sent to countries around the world but this is this largest to the Western Hemisphere. Four were sent to Bermuda in 2009 and two to El Salvador in 2012.

Associated Press writer Nedra Pickler in Washington contributed to this report.