Thirteen protesters accused of blocking a Heathrow Airport runway took part in a noisy protest outside court today.
Members of the Plane Stupid action group were due to go on trial charged with Aggravated Trespass and entering a security restricted area in July.
Green Party leader Natalie Bennett arrived at Willesden Green magistrates to support the defendants.
Other protesters unfurled banners and created a 'red line' inflatable barrage on the pavement outside.
One defendant, Rebecca Sanderson, reading from a statement, said the 13 were pleading not guilty because their actions were "reasonable, justified and proportionate.
Shadow Chancellor John McDonnell and Green Party mayoral candidate Sian Berry may give evidence as part of the defence case.
The trial is expected to last for two weeks.