Energy bill cap weighs on Centrica
Prime minister Theresa May's announcement of a cap on energy bills sent Centrica to the top of the FTSE 100's biggest losers by close of trade on Wednesday.
The parent company of British Gas saw its share price fall 6% to 179.30p.
Shares in rival SSE also sank, down 3.19% at £13.67.
Tesco was also a major faller, with its shares down 3.2% at 183.95p despite rising second quarter sales and the resumption of dividend payments.
Advertising giant WPP led the blue chip index higher, up 2.86% at £14.03.
Overall, the FTSE 100 closed marginally lower, down 0.01% at 7467.58.
The FTSE 250 finished 5.93 points down at 20,029.42
On the currency markets, the pound rose 0.24% against the dollar to $1.3700 and edged up 0.11% against the euro to €1.12830.