The U.S. State Department said both detainees, Tajik national Muhammadi Davlatov and Yemeni national Mansur Ahmad Saad al-Dayfi, were unanimously approved for transfer by six U.S. government departments and agencies

Authorities say the two men were at the U.S. detention facility at Guantanamo Bay, Cuba, for about 14 years. Their departure leaves 76 men at the facility, a controversial detention center that President Barack Obama pledged to close during his time in office.

The latest transfers are part of a renewed push by Obama to decrease the number of prisoners at the base.

It comes one day after another Yemeni detainee at Guantanamo was sent to Italy. More than a dozen other detainees are expected to be resettled in other countries in the coming weeks.

U.S. State Department Secretary John Kerry thanked Serbia for its "generous assistance" in accepting the detainees. "This significant humanitarian gesture is consistent with Serbia's leadership on the global stage," he said.

Obama would like to send some of the inmates to the United States for incarceration, but Congress has opposed the measure.

Obama issued an executive order in 2009 aimed at the eventual closing of Guantanamo, which critics argue has housed hundreds of prisoners, some of them for years, without formal charges and without trial. His efforts have been strongly opposed by Republican lawmakers who have cited the potential security risks posed by closing the facility.

The administration of George W. Bush opened the prison at Guantanamo in 2002, shortly after the U.S.-led invasion of Afghanistan, to hold foreign fighters with suspected links to the Taliban or al-Qaida.

The New York-based Center for Constitutional Rights said Tajik national Davlatov had been approved for release in 2008 and was slated to be sent to Tajikstan. But it said Davlatov argued he faced risk of torture in his home country and won a court injunction against his transfer there. The center criticized the Obama administration for making "no meaningful efforts" to transfer him for years.