A British judge is to rule on whether Ejup Ganic, a former Bosnian leader, should be extradited to Serbia over alleged war crimes.
The 64-year-old is 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.
His defence lawyers have 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.
A judge at the City of Westminster Magistrates' Court in central London, the British capital, is expected to make the decision after 13G on Tuesday.
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.