Five Greenpeace protestors who clambered on top of a British Airways passenger jet were convicted of various offences in court today.

The campaigners pleaded guilty to being in a restricted zone, boarding an aircraft and demonstrating in an airport at Uxbridge Magistrates' Court. They were each given an 18 month conditional discharge and will pay compensation to BA totalling £5,700.

In February, Anna Jones, Sarah Shoraka, Paul Della-Rocca, Frank Hewetson and Jens Loewe walked through an open door at Terminal 1 and stayed on top of the plane for two hours, hanging a banner from the tailfin reading: "Climate emergency - no third runway".

They were protesting against Labour's plans to build a third runway and sixth terminal at Heathrow. The plane they scaled had just arrived for Manchester and was refuelling for another domestic flight. The five waited until all the passengers had disembarked before walking through an open door and going "airside".

That week a Government consultation into proposals for Heathrow was completed. Ministers are expected to announce a decision on the proposed expansion later this year.

Anna Jones said: "Climate change can be beaten, but not by almost doubling the size of the world's biggest international airport. That's why we occupied the top of BA's Manchester to London flight. A huge number of planes leave Heathrow every day destined for cities easily reachable by train. If we invested in high speed rail instead of climate-wrecking runways we could begin to reduce the environmental impact of Heathrow instead of increasing it."

And Sarah Shoraka added: "The fight against Heathrow expansion is only just beginning. This new runway cannot and will not be built."