Ed Miliband at odds with energy firms over prices plan
Ed Miliband has insisted his plan to freeze gas and electricity bills will not lead to the lights going out - as suppliers stepped up their fight back.
The Labour leader made the promise on Tuesday - getting a rousing reception during his party conference speech.
But energy firms, business groups and coalition ministers have warned the plan could put future supplies at risk.
Shares in the two big energy firms listed in London - Centrica and SSE - fell by more than 5% on Wednesday.
Nick Robinson reports from Brighton.