The controversial radical Muslim cleric Sheikh Abu Hamza has been stripped of his UK citizenship.
Sheikh Abu Hamza praised Osama Bin Laden
Home secretary David Blunkett told BBC Radio 4's Today programme: "I have sent him a letter withdrawing his citizenship."
The Home Office confirmed the papers were delivered to the cleric on Friday.
However, a spokesman for Mr Hamza denied the reports, saying: "I am not aware that we have received any papers from the Home Office."
The preacher has 10 days to appeal.
Mr Blunkett said any appeal
would focus on "the way in which people are encouraged to take part in the jihad and fight us overseas".
Parliament voted for this to make holding our citizenship worth something
Home secretary David Blunkett
"I want to deal with people who our intelligence and security people believe are a risk to us," he added.
"If you encourage, support, advise, help people to take up training, if you facilitate them, then, of course, that takes you right over the boundary."
The move follows the introduction of new powers earlier this week allowing British nationality to be removed from people with dual citizenship who are believed to have acted against the vital interests of the UK.
Mr Blunkett told Today: "Parliament voted for this to make holding our citizenship worth something.
"People will have to work to earn it and they will be proud to have it
"And I'm proud to have done that."
Shadow home secretary Oliver Letwin said it was "important to protect the civil liberties of the country".
"I think it is reasonable that we should regard citizenship as a privilege
conveyed to people who have not been born here, with which certain
responsibilities should go," he told BBC Radio 4's World at One.
Tabloid newspapers and a number of MPs have pushed for Mr Hamza's removal from the country as he has angered many with praise for Osama Bin Laden and condemnation of Britain, the US and Israel.
Egyptian-born Mr Hamza has been resident in the UK since 1979, gaining British citizenship back in 1981.
A former Soho nightclub bouncer, Mr Hamza has become the controversial face of radical Islam in the UK.
He was a regular preacher at the Finsbury Park mosque in North London until his suspension by the Charity Commission last April.
His lawyer, Maddrassar Arani, said stripping him of British citizenship would leave him stateless and would therefore be a breach of his human rights.
Ms Arani told World at One: "Sheikh Abu Hamza doesn't have dual
nationality. He can't be rendered stateless. If they do that, they will be in
breach of the (Nationality, Immigration and Asylum) Act itself."
In 1999 Abu Hamza was questioned by Scotland Yard detectives on suspicion of terrorism offences in Yemen.
He was held for several days before being released without charge. He has always maintained his innocence.
The Yemeni authorities had requested his arrest and extradition, claiming he was linked to plots to bomb targets there.
But Mr Hamza came to real public prominence in the aftermath of September 11 when he praised the terrorist attacks on the US.
Home Office lawyers believe Mr Hamza's Egyptian nationality has never been revoked.
As a result under section four of the Asylum, Immigration and Nationality Act 2002 the radical cleric could be stripped of his citizenship.
Until a Deprivation Order is upheld, Mr Hamza will remain a British citizen and will not be able to claim asylum in the UK.
This will be the first test case under the new powers.