EDE, Netherlands (AP) — Hundreds of climate protesters blocked private jets from leaving Amsterdam’s Schiphol Airport on Saturday in a demonstration on the eve of the COP27 United Nations (UN) climate meeting in Egypt.

Greenpeace and Extinction Rebellion protesters sat around private jets to prevent them leaving and others rode bicycles around the planes.

Dewi Zloch of Greenpeace Netherlands said the activists want “fewer flights, more trains and a ban on unnecessary short-haul flights and private jets.”

Military police said they arrested a number of protesters for being on the airport’s grounds without authorization.

Responding Friday to an open letter from Greenpeace, Schiphol’s new CEO Ruud Sondag said the airport is targeting “emissions-free airports by 2030 and net climate-neutral aviation by 2050. And we have a duty to lead the way in that,” but conceded it needed to happen faster.

More than 120 world leaders will attend this year’s UN climate talks at the Red Sea coastal resort of Sharm el-Sheikh starting Sunday.

Thorny issues up for discussion at the Nov. 6-18 talks, including further cutting greenhouse gas emissions and boosting financial aid for poor countries struggling with the impacts of climate change.