Downing Street has described EDF Energy's price rises as "very disappointing":
It is up to energy suppliers to explain their prices to their customers.
While we can't control world energy prices, we have been working very closely with the energy companies to make it easier for people to switch to find cheaper deals.
We want to ensure customers get the lowest tariffs.
That is why we are going to use the law to help people get the best deals.
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