The Minister for Communications, Energy and Natural Resources, Eamonn Ryan, has refused licences to two companies who wanted to explore for uranium in Co Dongeal.
It signals a wider policy decision to ban such activity in Ireland.
Mr Ryan said the mostly likely end use of any uranium that would be extracted, would be for nuclear energy generation.
He said it would be hypocritical to permit the extraction of uranium for use in nuclear reactors in other countries, while the nuclear generation of electricity is not allowed in Ireland.
