BRITISH gas promises to protect its most vulnerable customers as it announced the first price increase since 2013.

Electricity prices will rise by 12.5 per cent as of September 15 while gas prices remain the same.

The average annual dual fuel bill for a typical household on a standard tariff will increase by 7.3 per cent, seeing their bill rise from about £76 to £1,120.

However, Centrica plc, which owns the utility company, said it is one of the last suppliers to introduce a price rise.

For more than 200,000 customers who automatically receive the Warm Home Discount, British Gas has promised to credit their account with £76.

The change will affect 3.1million customers.

British Gas were unable to inform the Gazette how many of those customers are in East Anglia.