British citizens will be extradited for what critics have called a "thought crime" under a new European arrest warrant, the Government has conceded.Campaigners fear they could even face trial for broadcasting "xenophobic or racist" remarks - such as denying the Holocaust - on an internet chatroom in another country.The Government has undertaken that if such "offences" take place in Britain the perpetrators would not be extradited - but it will be for the courts to decide the location of the crime.This opens up the prospect of a judge agreeing to extradite someone whose observations, though made in Britain, were broadcast exclusively in a country where they constitute a crime....The proposed EU directive would extend the offences of racism and xenophobia to include discrimination on the grounds of religious conviction - something that was dropped by the Government more than a year ago following fierce opposition....However, Britain has been forced to concede a review after two years at which point the directive could be extended to opinions that are simply considered offensive and not just those likely to incite violence.