The UK Government shelved the plans in the late 1980s due largely to cost issues and local environmental concerns. However, this was before recent huge rises in the price of energy, and before global warming had started to be taken seriously. In April 2006 the Welsh Assembly approved the idea of utilising the tidal power, but the RSPB has raised serious concerns about the effect on the mud flats, that have European Environmental protection status, and the UK government Energy Review published later in the year did not endorse the scheme.