Muscat (AFP) - Oman said it received 10 inmates from the US detention centre at Guantanamo Bay Monday, as outgoing President Barack Obama looks to reduce the number of prisoners there before leaving office.

Neither the sultanate's foreign ministry nor the US defence official who confirmed the transfer would disclose the nationality of the inmates who would reside in the Gulf Arab country on a temporary basis.

"At the request of Sultan Qaboos and the US government for a solution to the question of Guantanamo detainees, 10 of these detainees arrived today in the sultanate to reside here temporarily," the ministry said, quoted by the official ONA news agency.

In Washington, the US official said: "We can confirm the transfer of 10 detainees from the detention facility at Guantanamo Bay to the government of Oman. We have nothing further at this time."

The latest transfers leave the number of Guantanamo detainees at 45, according to the official.

Ten days ago, four Yemenis were sent from the US prison on Cuban soil to Saudi Arabia.

Early this month, Obama's spokesman Josh Earnest said he would expect "additional transfers" before the Democrat hands power to President-elect Donald Trump on January 20.

Obama vowed to close the Guantanamo detention facility when he took office in 2009, arguing that detention without trial did not reflect American values.

But faced with Pentagon foot-dragging and stubborn Republican opposition to shutting down the prison, his administration has focused on whittling down the number of inmates.

Trump has called for a freeze on transfers.

On January 3, he tweeted that "there should be no further releases from Gitmo. These are extremely dangerous people and should not be allowed back onto the battlefield."

Only a handful of those who remain at the prison have started moving through US military tribunals, including the alleged plotters of the 9/11 attacks.

Others remain in legal limbo -- not charged but deemed too dangerous to release.