Australian former Guantanamo Bay detainee Mamdouh Habib has told SBS he doesn't believe US President Barack Obama's moves to close the centre are genuine.
Mr Habib was held in the detention centre in Cuba for almost four years, between 2001 and 2005.
"I'm going to tell him again. I told him in 2011, you're a liar when you mention you're going to close Guantanamo Bay. I'm going to tell him now - 2016 - you are the biggest liar," Mr Habib said.
Mr Obama unveiled his road map to close the facility on Wednesday, but Mr Habib believes US authorities are “never" going to close it.
"He [isn't] even thinking to close one door of Guantanamo Bay, because he can’t afford it," Mr Habib said.
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"Let him face me, face-to-face, and he tell me 'Habib, we're going to close Guantanamo Bay'."
Mr Habib was arrested by US authorities in 2001 in Pakistan. He was released without charge in 2005.
He said investigations into the facility needed to take place.
"The investigations have to be done by us, by people who have been there, we know every single part of Guantanamo.. there are too many secret places in Guantanamo Bay," he said.
“Too many different places they use for torture, they have women, they have kids, they have new-born babies. It has to be investigated by honest people. I would love to investigate Guantanamo Bay and I would point my finger at every crime and every murder."
US Republican candidates Ted Cruz, Donald Trump and Marco Rubio have spoken out against Mr Obama's plan to close the centre.
Watch an extended interview with Mamdouh Habib:
