York Minster was among the churches taking part
Bells in churches across Britain have chimed 350 times to press for a deal at the Copenhagen climate conference.
York Minster and Westminster Cathedral were among churches which joined a world event coinciding with a service in the Danish capital.
The aim was to highlight the 350 parts per million some developing nations say is the safe upper concentration for carbon dioxide in the atmosphere.
Bells are being rung at 1500 local time in churches across the world.
Other countries taking part in the bell ringing include New Zealand, Australia, Brazil, Canada, Belgium, France, Germany, the Netherlands, Switzerland, Sweden and the US.
The ecumenical service at the Lutheran Cathedral in Copenhagen was attended by Queen Margarethe of Denmark, as well as politicians and delegates taking part in the climate conference.
The Archbishop of Canterbury, who last week at an Environment Service in London said human well-being relied on the well-being of the world, also attended the service.
The initiative was organised by the World Council of Churches, which represents more than 500 million Christians.
Although some rapidly industrialising countries are campaigning for a limit on carbon of 450 parts per million, poorer countries - particularly those at risk of flooding rivers and rising sea levels - want the target pegged at 350 parts per million.