LONDON, March 13: The House of Lords brought to an abrupt but perhaps temporary halt Washington’s efforts to break up international cartels, by ruling on Wednesday that a British executive cannot be extradited to the US for committing a white collar crime when it was not defined as such under British law.

Ian Norris, the former chief executive of Morgan Crucible, is accused of price-fixing during 1990s. The US has been trying to get him extradited to Pennsylvania where he is facing charges to the effect.

The Lords’ ruling that Mr Norris should not be sent abroad to stand trial for alleged price-fixing is based on the fact that cartel activity was not a crime in the UK until 2003.

Under Britains extradition agreement with the US, suspects can be extradited only if both jurisdictions defined the action as such at the time of its happening. Mr Norris is alleged to have been involved in a global cartel on carbon products between 1989 and 2000 when price-fixing was not considered a crime in Britain.

When the US prosecutors sought to classify Mr Norris’s alleged conduct as the English common law offence of conspiracy to defraud, the Law Lords dismissed the argument on the grounds that Mr Norris was not charged with any “aggravating” conduct.