Malcolm Wicks warned of devastation to wildlife from global change
UK Energy Minister Malcolm Wicks has attacked Europe's largest conservation charity for opposing the proposed Severn Barrage.
He told the Welsh grand committee the RSPB did not understand the impact of climate change and sought the "comfort" of saying no to environmental projects.
But its backers argue that it could help solve a growing energy crisis, providing 5% of the UK's needs.
The RSPB said that amount of renewable energy could be made at half the cost.
A feasibility study on the project by the Welsh Assembly Government and UK Government was announced in January.
The £15bn dam would span the Severn estuary from Lavernock Point, near Cardiff, to Brean Down, near Weston-super-Mare.
Mr Wicks told MPs the RSPB was "clearly not understanding that unless we are prepared to take some courageous action on climate change the devastation of species will be truly enormous".
"It is the duty of a sensible NGO (non-governmental organisation) supported by the public that occasionally they say yes to projects and (are) not always seeking the comfort zone of saying no to a barrage, no to a windfarm, no to this, no to that," he said.
"There needs to be a responsibility and a seriousness in all organisations, especially the environmental ones," Mr Wicks added.
But he also informed the committee the plans could be dropped in a year if the project failed economic and environmental tests.
He said the UK government would not press ahead with the scheme if preparatory work proved negative and promised the alternative of lagoons would also be closely looked at.
Mr Wicks said: "We take this assessment very, very seriously. This is a very special ecological area, it is unique and we have to approach this with great care.
"Our programme of work at the moment is to ensure that if in a year's time our initial assessments were showing that there was a big show-stopper, that this just wasn't on for environmental or economic reasons, we will stop it, we will stop it."
The RSPB, which has a million members, has warned thousands of birds, spawning salmon and other fish will be put at risk if the barrage is built.
It has also argued that it would damage number of sites protected by European, international and British law.
Last week an independent report, commissioned by environmental groups including the RSPB, concluded the power generated by the proposed barrage could be produced more cheaply using other green technologies.
But Mr Wicks was urged by former Welsh Secretary Peter Hain to press ahead with the Severn Barrage assessment.
Mr Hain said tidal lagoons would generate only half the power.
"There will be no birdlife or wetland life if climate change wreaks its terrible havoc as it undoubtedly will," he said.
Mr Wicks will meet Welsh Environment Minister Jane Davidson on Thursday and visit the site of the proposed barrage on Friday.
Reacting to the minister's criticism, the RSPB said it had "many experts" on climate change and was part of the Stop Climate Chaos coalition which campaigned for a Climate Bill.
The charity's director of conservation, Mark Avery said: "Check our website to judge how seriously we take climate change.
"Mr Wicks is ignoring the difficult issue facing the government over the cost of the Severn Barrage - the energy it produces can be produced at half the cost by other renewable technologies.
"Why should we spend £15bn, at least, on a barrage when the same amount of renewable energy could be produced at half the cost?
"Does Mr Wicks think that wasting £7.5bn is good government policy?"'