MP Peter Luff will raise the findings of the report with the home secretary
Radical Muslims are spreading extremist propaganda and promoting jihad from inside UK jails, a report has claimed.
Counter-extremism think tank the Quilliam Foundation said radicals were also being allowed to lead prayers.
And its report said extremist cleric Abu Qatada had issued fatwas from Long Lartin prison in Worcestershire where he is awaiting deportation.
The Ministry of Justice said it had a dedicated unit to tackle the risk of extremism and radicalisation in prison.
The Quilliam Foundation said the study, to be published on Monday, was based largely on accounts sneaked out of prisons by high-profile extremists.
The report said: "Prominent pro al-Qaeda ideologues such as Abu Qatada have been able to smuggle messages out of prison to their supporters.
"Other convicted extremists have issued pro-jihadist statements from prison while others have appeared on Islamic TV stations from within prison.
"In 2008 and 2009, two of the most prominent Arab jihadists imprisoned in the UK released pro-jihadist propaganda and fatwas from within Long Lartin prison.
"Adel Abdel Bary, a leader of Egyptian Islamic Jihad, produced written pro-jihadist tracts from within prison aiming to refute criticism of al-Qaeda, while Abu Qatada issued fatwas from within prison which legitimised jihadist attacks worldwide."
Mid-Worcestershire MP Peter Luff, whose constituency includes Long Lartin, plans to raise the report's findings with Home Secretary Alan Johnson and Justice Secretary Jack Straw.
Mr Luff said: "In my view the courts have, in the past, failed to protect us by allowing the release of dangerous individuals from Long Lartin and other prisons, and by delaying the deportation of many others.
"While these deeply dangerous men remain in British custody, we must be absolutely confident that they can do no harm - and these revelations suggest we cannot be confident of that.
"The government must move quickly to address the exceptionally serious issues this report raises."
The Ministry of Justice said the Quilliam Foundation did not contact the department and did not apply to visit any jails or speak to prison staff.
A spokeswoman said: "We are extremely skilled in managing all challenging and dangerous criminals, and adapting to evolving risks and dangers.
"We run a dedicated, expert unit which leads work to tackle the risk of extremism and radicalisation in prison.
"All our high-security prisons operate enhanced monitoring and intelligence-gathering on those convicted or suspected of involvement in terrorism or extremism."