FTSE 100: 7553.32 ▼ -78.01 (-1.02%)
Shares in the British Gas owner fell 2.9% to 196.6p after UK business secretary Greg Clark took to the Today programme to defend the policy after Centrica used a trading statement yesterday to criticise the plans.
'Centrica does not believe in any form of price regulation,' it said in the statement. 'Evidence from other countries would suggest this would lead to reduced competition and choice, and potentially higher average prices.'
But Clark said the government was acting to curb 'abusive' behaviour from the 'big six' power companies, saying the Competition and Markets Authority (CMA) had estimated £1.4 billion of overcharging a year.
Centrica is seen as the most exposed to the Tories' price cap plans, but SSE (SSE) would also be affected. Its shares were down 1.2% at £14.32.
Joining Centrica at the bottom of the index was Micro Focus (MCRO), down 8.2% at £24.22 after the software group warned revenues at Hewlett-Packard Enterprise, the US company it is buying, had fallen 10% in the last quarter.
But miners helped the FTSE 100 shoulder those losses, rallying as the copper price rebounded. Risers included:
Among 'small cap' stocks, Sepura (SEPU) surged 22.7% to 12.6p after the government cleared the way for its £74 million acquisition by China's Hytera Communications (002585.SZ).
Business secretary Greg Clark's approval of the deal means it will no longer need to be referred to the CMA.