Mi5 officers witnessed detainees being chained, hooded, waterboarded and subjected to mental abuse, according to the publication.
The ISC has reportedly described a forthcoming investigation as a "substantial inquiry into the role of the UK government and security and intelligence agencies in relation to detainee treatment and rendition."
A date for the ISC hearing has not been formally set.
The 45-year-old from Birmingham claimed he had been interrogated by Mi5 and Mi6 agents alongside 15 British citizens held indefinitely at the facility. He charged that US and British intelligence worked hand-in-hand for the entirety of his detention since 2002.
The US Senate revealed the Central Intelligence Agency's use of torture techniques at Guantanamo as part of the War on Terror in 2001-06 in December 2014.