Fresh attempts by Tony Blair to ban a radical Muslim group are facing opposition from the police and Home Office officials, the BBC has learned.
Tony Blair said last year he wanted to ban Hizb ut-Tahrir
It is understood no direct links have been found between Hizb ut-Tahrir and a support for violence.
Home Office officials are also understood to be concerned a successful legal challenge to a ban would be highly damaging.
Hizb ut-Tahrir says it is opposed to violence.
The political party advocates the creation of an Islamic state across the Middle East.
Last year the prime minister said he would like to ban Hizb ut-Tahrir but the group has remained off the list of proscribed groups.
Number Ten has been the driving force behind a fresh look at banning Hizb ut-Tahrir, or HT.
The Home Office has been actively considering proscribing the organisation to coincide with Mr Blair's current visit to Pakistan, which has a ban in place.
But it is understood that neither the police nor the security services have been able to find direct links between the group and violence.
Senior police officers do not think a ban would be helpful, the BBC understands.
But both Mr Blair and Home Secretary John Reid are understood to be in favour.
HT spokesman Imran Waheed said the group was not violent.
"It is now abundantly clear to everybody despite slander, vilification and distortion of our views that Hizb ut-Tahrir is a political party that is at the forefront of challenging tyranny and dictatorship - far away from the lies of violent extremism and terrorism.
"From the very beginning, since the proposal to ban our organisation was first mooted, we said that this was due to the pressure placed on Britain by the dictators of the Muslim world, who wanted Hizb ut-Tahrir's political work to be stifled," he said.
"This is further evidence that this was the case."
A BBC File on 4 and Newsnight investigation, screened on Tuesday, spoke to a mole inside a cell said to be connected to the organisation.
He claimed it makes recruits commit crimes to test their loyalty and uses brain-washing techniques to incite them to hate "non-believers".
It also revealed that a leading member of the group, Abid Javaid, is working as a senior official at the Home Office.
A Newsnight investigation in 2003 discovered that HT's website promoted racism and anti-Semitic hatred, called suicide bombers martyrs, and urged Muslims to kill Jewish people.
In Denmark, HT's spokesman has been found guilty of distributing racist propaganda.
The group is banned in some countries.
Germany and Russia are among the countries in which it is illegal, while it has also been officially targeted by Central Asian states such as Uzbekistan.
HT said in a statement on Wednesday it was a non-violent Islamic political group.
"We are a non-violent organisation that has worked for over 10 years in Britain," the statement said.
"For the avoidance of any doubt we do not advocate or otherwise promote the use of violence or any criminal activity against civilians in the UK or anywhere else in the world."