Plans to drill for oil off the coast of Wales have been put on hold indefinitely after the government ruled that more research needs to be carried out into the likely impact of exploration on a school of dolphins.

While three energy companies recently applied for licences to explore parts of Cardigan Bay, energy minister Malcolm Wicks has now ruled that more research needs to be carried out into the population of around 250 bottlenose dolphins.

Mr Wicks stated: "My officials visited Cardigan Bay to hear local views first hand and we also received numerous comments from interested parties concerned about the resident bottlenose dolphin population there.

"At the moment we don’t know enough about the number and distribution of the dolphins to be able to decide if it would be safe to explore that area."

Though the ruling is not final, a new report from St Andrew's University on the effect of oil exploration on sea mammals suggests that it is highly unlikely that the drilling plans will get the green light for the foreseeable future.

However, he added that a similar project in the Moray Firth in Scotland, which is also home to bottlenose dolphins, is likely to go ahead as enough is known about them to ensure that any project is carried out in a manner which minimises any impact on the local wildlife.