Climate change protesters gathered in Oxford this morning at the headquarters of a carbon offsetting company.

The protest, involving about 15 people, started at 9am when five demonstrators, dressed as red herrings, climbed onto the building in Magdalen Road and unveiled a banner, which said: "Carbon offsetting equals red herring".

Some of the protesters went into the offices of Climate Care to lobby the managers.

The group, Plane Stupid, were involved in this week's environmental protest at Heathrow Airport. Thames Valley Police were monitoring the protest this morning, but so far no arrests have been made.

They claim that carbon offsetting is a not a responsible solution for tackling climate change. Joss Garman, a spokesman for Plane Stupid, said: "We want to highlight to members of the public who give money to Climate Care that it does not neutralise the impact.

"Paying people in developing companies to pollute less so we can pollute more is not a responsible solution to climate change."

Michael Buick, a spokesman for Climate Care, said: "The point is one of principle. The campaigners don't think it is acceptable to take responsibility for your impact on the climate by paying for offsetting.

"There is no green flight option but what you can do is say 'I will avoid flying if I can' and if I can not I will pay for offsetting."

Passengers on flights can pay an offset fee to Climate Care, who then invest the money in carbon-reducing projects worldwide.