An Inuit leader will appear as a defence witness in the trial of six Greenpeace protesters who attempted to shut down Kingsnorth power station last year.

Aqqualuk Lynge will give evidence from Greenland via a videolink.

Mr Lynge is president of the Inuit Circumpolar Council representing approximately 160 000 Inuit living in the Arctic regions of Alaska, Canada, Greenland and Chukotka, Russia.

He will be among the last witnesses called to support defendants' claims they had a lawful excuse to cause £30,000 of damage at the Hoo plant on October 8 2007.

On Wednesday James Hansen, director of NASA’s Goddard Institute for Space Studies, appeared at Maidstone Crown Court.

He told the court that Kingsnorth Power Station could be responsible for causing the loss of several hundred species of animals and plants due to climate change over its lifetime.

He added: “By cutting off the emissions at Kingsnorth for two days, you could say that one species is saved.”

Prof Hansen called for a halt to the building of new coal fired power stations unless they have the facility for carbon capture, and said existing ones should be fazed out over the next 20 years.

Asked in court what his message to Gordon Brown would be, Prof Hansen said: “I would ask him to make a clear public statement for a moratorium on new coal-fired power plants that do not capture C02. He said: “There is an immediate need to protect property from carbon emissions.”

He added that continuing with a “business as usual” approach would see the planet passing its climate change tipping point, putting it on a disastrous future course.

The jury were told on Monday how the six defendants entered the power station at 6.30am on October 8 2007, wearing orange boiler suits and hard hats bearing the Greenpeace logo.

Five of the group began to scale the power station chimney with the intention of painting the slogan ‘Gordon Bin It’ on the side while the sixth defendant Tim Hewke remained outside the power station in contact with those inside and co-ordinating the protest.

Prosecuting John Price, said: “By the time the five defendants climbed down at 1.30pm the following day, after E.ON obtained a High Court injunction they had managed to paint only Gordon on the side of the chimney.

“This cost the company a few pence short of £30,000 to remove."

The defendants Tim Hewke, 47, of Chegworth Road, Harrietsham; Kevin Drake, 43, of High Street, Chapmanslade, Wiltshire; Ben Stewart, 33, of Alkham Road, Stoke Newington; William Rose, 27, of Laurier Road, Kentish Town; Emily Hall, 33, of Smyrna Road, Kilburn and Huw Williams, 40, of Chesterfield Drive, Burton Joyce, Nottinghamshire have all pleaded not guilty to the charge on the grounds they had a lawful excuse.

The chimney damage at Kingsnorth was necessary in order for them to protect other property in Kent and the world threatened by climate change, the court heard.