Energy Secretary Edward Davey insists that there will not be a direct subsidy of new nuclear, but cannot say the cost will not end up with the taxpayer or consumer.
He says that the Horizon deal with Hitachi is "a real vote of confidence from foreign company" in the UK.
Spades will be in the ground at Oldbury and Anglesey in 2016 or 2017 at the very earliest.
More top news
Staff working for AMs made two claims of sexual assault against BBC staff and one against a politician.
Dawn Butler has spoken out about the peer’s controversial tweet, which has since been deleted.
Profile of David Black, who was killed in November 2012.