An anti-nuclear protester who set out on a night-time bid to disarm a Trident submarine has told a Court she was acting under international law.

Campaigner Sylvia Boyes, 57, of Keighley, allegedly went armed with hammers and screwdrivers on the night of November 23, 1999 to prevent the Vengeance submarine dock at Barrow in Cumbria going into military service.

Manchester Crown Court heard how she and Open University lecturer River, formerly Harold Wright, had planned to do as much damage as possible to the "war machine" without harming anybody or the surrounding community.

Under questioning from her barrister Terence Munyard, Mrs Boyes, a member of the Ploughshares Anti Nuclear Group said she had exhausted all peaceful means of protest and had been forced into direct action.

She said that in 1996 the International Court of Justice had condemned nuclear weapons as illegal.

"The president of ICJ said the existence of nuclear weapons was a threat to humanitarian law and that the use of nuclear weapons was generally against humanitarian law."

She said the action took place when it did because the submarine was about to be commissioned.

"It was not yet a military vessel but it was due to be commissioned into the Navy.

"We felt this was our last chance to prevent this horrendous war machine being deployed."

Under questioning from River, representing himself, she said the case of a group of women who had disarmed Hawk bomber planes and had not been imprisoned gave her the legal courage as they had proved the planes were about to be used in action by the British Government, against international law.

Mrs Boyes had with her on the night a film crew from BBC TV's Everyman programme which had been recording her life before the attempted attack.

Prosecution barrister Elizabeth Nicholls claimed Mrs Boyes' and Rivers' actions had been no more than a "publicity stunt".

She said: "Surely if this was a serious attempt to breach high- level security, it is ludicrous to have a film crew with you?"

Mrs Boyes said in hindsight she wished she had not taken the crew with her but added: "People convinced me it would be useful to bring our views to the wider public.

"I'm not the sort of person who does publicity stunts. They were there to film but not just because I was climbing over the fence."

Both Mrs Boyes and River deny conspiring to commit criminal damage. The case continues.