A British court has blocked the extradition of Ejup Ganic, a former Bosnian leader, to Serbia, where he is accused of war crimes.

The 64-year-old was accused of ordering the killing of more than 40 Yugoslav army soldiers retreating from Sarajevo at the start of the 1992-95 Bosnian war, when he was president.

But Timothy Workman, district judge at London's City of Westminster Magistrates' Court, said there was evidence that the trial against Ganic could be "politically motivated".

His defence lawyers had previously argued that two previous investigations found he had no case to answer and there was insufficient evidence to warrant a trial.

They have also contested the suggestion that Ganic was in charge at the time of the attacks.

Ganic was arrested at Heathrow Airport on March 1 as he attempted to leave Britain after attending a degree ceremony at the University of Buckingham.

Serbia has said Ganic and a number of other people are suspected of war crimes, and blames them for the 1992 attack on a Yugoslav convoy in Sarajevo, when more than 40 soldiers were killed.