Heathrow airport's owner has won a high court bid to ban certain environmental protestors from taking part in a demonstration near the site.
BAA had sought the injunction over the Camp for Climate Action, a protest due to take place between August 14th and 21st.
Organisers of the protest say that thousands of people are due to gather near Heathrow for "eight days of education, sustainable living and direct action against the root causes of climate change".
But BAA had said that it was seeking the injunction against unlawful behaviour in order to protect passengers from direct action it claimed some protestors were intent upon carrying out.
In today's ruling one protest group, Plane Stupid, was banned from taking part in direct action although BAA's injunction had named other campaigning groups.
Mrs Justice Swift said that the only way to prevent the potentially "serious and damaging" consequences of any unlawful direct action was to grant an injunction.
She stressed that there was a risk that a terrorist group might seek to use any disruption by protestors in order to carry out a terror attack.
BAA has welcomed the ruling as a victory in its efforts to prevent Heathrow passengers from being "harassed" or "obstructed" by direct action.
Speaking outside London's high court after the ruling a spokesman for the company said the airports operator had a responsibility to do "everything we can" to guarantee the safety and comfort of Heathrow passengers, with over a million people expected to pass through the airport during the period the climate change protest is due to take place.
However protestors have claimed that BAA's widespread legal bid to curb campaigners has failed and have vowed that the demonstration will continue, despite the banning of one group.
London mayor Ken Livingstone had previously accused BAA of attempting to bring about a "serious infringement of civil liberties", claiming that the original injunction sought by the airports operator would have affected around five million people because of restrictions the company had sought to impose on protestors travelling on the capital's transport networks at the time of the demonstration.