A British high court judge has halted the extradition of Abu Hamza al-Masri to the US after the radical cleric lodged a last-ditch legal appeal, the judiciary office said.

The judge issued "interim injunctions" barring the removal of Egyptian-born cleric Abu Hamza and a second "terror" suspect, Khaled al-Fawwaz, pending a hearing in open court which will happen "urgently", a spokesperson said on Tuesday.

The European Court of Human Rights on Monday upheld an April 10 ruling that it made approving the extradition from Britain of Hamza, Fawwaz and three other suspects to the US.

'Delaying tactic'

"Applications have been lodged by Kamel Mustafa Mustafa (aka Abu Hamza) and Khaled al-Fawwaz seeking injunctions preventing their removal from the UK," the judiciary office spokesperson said.

"A High Court judge has considered the applications on the papers and adjourned the cases to a hearing in open court."

The grounds for the appeal by Abu Hamza and al-Fawwaz were not immediately clear. Their lawyers did not return calls seeking comment.

A British government source told the AFP news agency the appeals by the two terror suspects were a "delaying tactic".

The government would continue working with the police and the US authorities to ensure the extraditions went ahead as quickly as possible, the source said.

Hamza, the former preacher of the Finsbury Park mosque in north London, is wanted in the US on charges including setting up an al-Qaeda-style training camp in the US state of Oregon.

He is currently serving a seven-year jail sentence in Britain for inciting followers to murder non-believers in speeches on the streets of London.