Bord Gáis Éireann has invited Blackstone Group LP and power companies Viridian Group Ltd and Centrica Plc to make final offers for its retail unit by Nov 25, according to people with knowledge of the matter.

The Government has refused to comment on the effect that the withdrawal of Tenaga Nasional will have on the bidding process for the sale of Bord Gáis.

Following the withdrawal of one of the three bidders from the sales process, it now looks unlikely that Bord Gáis’s retail and power generation division will be sold before 2014.

Viridian Group Ltd — Northern Ireland’s largest energy supplier — hired Macquarie Group Ltd to advise on its bid for the retail and power generation unit of Irish state-owned gas company Bord Gáis, people with knowledge of the matter said.