Image copyright Getty Images Image caption Guantanamo Bay is being used to detain what the US government calls "enemy combatants"

The Pentagon plans the transfer of 17 Guantanamo Bay detainees in the coming weeks - a move that would cut the US prison's population to 90, reports say.

US media quote officials as saying Defence Secretary Ashton Carter has already told Congress about the move.

It would reportedly be the largest number of detainee transfers in a single month since 2007.

President Barack Obama wants to close the controversial jail in Cuba, set up during the "war on terror" in 2002.

It is being used to detain what Washington calls "enemy combatants", following the 11 September 2001 attacks in the US.

The first 20 detainees were transferred to the facility on 11 January 2002, and a total of 780 men have been held since then - the vast majority without charge or criminal trial.

Restrictions tightened

Mr Carter recently notified Congress about the planned transfer of 17 lower-level detainees, officials familiar with internal deliberations were quoted as saying by the New York Times newspaper.

Separately, a senior US defence official told the AFP news agency: "We found homes for the 17 [detainees]", adding that several countries had agreed to take them in.

All the officials spoke on the condition of anonymity.

The New York-based Human Rights First organisation welcomed the reported move.

"It is encouraging to see President Obama take decisive action toward transferring these detainees - who have been cleared for transfer by all relevant national security agencies - out of the detention facility," said Human Rights First's Daphne Eviatar.

"But the simple fact remains that the president needs to continue making this a priority if he intends to follow through on his promise to shutter Guantanamo before he leaves office," she added.

President Obama is trying to shut the Guantanamo detention facility before he leaves the White House in 2017.

It is believed that 20 prisoners have been transferred so far in 2015.

The Republican-dominated Congress has tightened restrictions on transfers from the prison, requiring the Pentagon to report that security standards have been met at least 30 days before any such move.

Lawmakers are also resisting attempts to transfer any prisoners inside the US.