Fawzi al-Odah
Protesters hold a portrait of Fawzi al-Odah at a rally outside the US embassy in Kuwait City calling for the release of Kuwaiti prisoners in Guantanamo Bay. YASSER AL-ZAYYAT/AFP/GettyImages

Republicans have criticised the transfer of a suspect Islamist militant held at the US detention facility at Guantanamo Bay for almost 13 years to his native Kuwait.

Fawzi al-Odah one of the longest-held prisoners at the military base in southeast Cuba, where he has been locked up without being charged since February 2002, has been boarded on a flight from the Caribbean island and sent home.

"[This is] yet another dangerous example of the Obama administration's misguided motivation to empty and then close Guantanamo rather than protect the national security interests of the United States," said US Sen. Kelly Ayotte, from New Hampshire.

Obama has repeatedly pledged to close Guantanamo bay prison, which first opened in January 2002 and currently holds 148 people.

Ayotte, a member of the Senate Armed Services Committee is a chief proponent of keeping the prison open.

Al-Odah's transfer came at the end of a lengthy legal battle by his family supported by the Kuwaiti government.

According to the transfer agreement, he is to serve at least one year at a militant-rehabilitation centre in a Kuwaiti prison, but might be eligible for to leave for part of the day to work or see family within six months.

He was arrested in Pakistan on suspicion of having ties to al-Qaeda or the Taliban - something he denies.

Odah and his family maintained he travelled to Afghanistan to teach the Koran. His father Khalid al-Odah, claimed in interviews with the Associated Press that he been wrongly turned over to US forces in exchange for a bounty.

His lawyer, Eric Lewis, said the 37-year-old now hopes to get back to a normal life.

"There's no bitterness, there's no anger," Lewis said. "There's just excitement and joy that he will be going home."

His transfer came as a review panel tasked with re-evaluating prisoners at Guantanamo ruled he did not represent a "continuing significant threat".

Obama has repeatedly pledged to close Guantanamo bay prison, which first opened in January 2002 and currently holds 148 people.