Employment Minister Sir Reg Empey has written to Taoiseach Brian Cowen urging him to prevent the potential sale of Northern Ireland's electricity network to Irish firm ESB, the Belfast Telegraph can today reveal.
In a frank letter, seen by this newspaper, the Ulster Unionist leader told the Irish premier that "such a transaction would be unacceptable to me and my party".
NIE confirmed yesterday its parent Viridian is in negotiations with ESB, which is owned by the Irish government, over the sale of its transmission and distribution business.
Sir Reg has warned Mr Cowen that any such acquisition "flies in the face of current European policy, which is urging member states to divest of owning energy transmission systems".
He has also written to Enterprise Minister Arlene Foster demanding she does everything possible to stop the transaction.
While currently owned by a private company, Sir Reg said the electricity grid is Northern Ireland's "most strategically important infrastructure asset" and is meant to be held in trust for all electricity customers.
"I wish to make it clear that I am implacably opposed to such a transaction occurring while ESB remains a state-owned body," said Sir Reg. In his letter to the Irish Prime Minister, he added: "For these assets to be purchased by the government of a third country irrespective of the agency used for such a transaction would be unacceptable to me and my party."
He urged Mr Cowen to put an end to the proposed acquisition and threatened to call in the European Commission to examine if he did not get a positive response. ESB controls the electricity network in the Republic.
Following speculation over the weekend NIE confirmed its owner Viridian was in discussions with ESB about a "possible conditional sale" of the transmission business.
"These discussions may or may not lead to a transaction," it said.
ESB also said it was talking with Viridian's ultimate owner Arcapita, the Bahrain-based investment fund which bought the company in 2006 for £1.6bn.
The Utility Regulator said it will be monitoring the situation.