Energy supplier RWE Npower will on Saturday increase its household gas and electricity bills to new highs, raising the prospect of average UK energy bills breaking through £1,000 ($1,975, €1,337) a year for the first time.

On Friday, Npower said that its gas bills would rise by an average of 17.2 per cent and its electricity bills would rise by an average of 12.7 per cent from Saturday, the first energy supplier to increase its mainstream tariffs since the start of last year.