Peace activists who took direct action to try to stop military hardware leaving for Iraq cannot argue in defence to criminal charges that they were trying to prevent an illegal war, the House of Lords ruled unanimously yesterday.

The activists included 14 Greenpeace volunteers convicted over activities at Marchwood military base in Southampton in 2003. They were joined in the appeal by five people awaiting trial on charges relating to entering RAF Fairford in Gloucestershire in 2003, and another convicted of aggravated trespass and criminal damage after entering the base.