Despite the announced profits increase, British Gas owner Centrica would not rule out further rise in tariffs this winter, blaming "upward pressure on costs".
We will keep prices as low as we can for as long as we can. If prices do have to go up, we will delay it for as long as possible.
Mr Luff said the Government-backed ECO (Energy Companies Obligation) scheme, which helps customers with boiler repair or replacement or insulation costs, would "inevitably impact on customer bills ultimately".
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Philip Hammond has dismissed concerns that abolishing stamp duty for first-time buyers will push up house prices.
Elsewhere it will be largely sunny, though with gusty winds at times, and a few showers likely in places.
Heavy rain has caused widespread flooding and travel disruption across north west England and North Wales.