Government minister Liam Byrne has apologised for using House of Commons envelopes for sending mail to residents in Birmingham and has blamed a volunteer for the gaffe.

The taxpayer-funded envelopes are for official parliamentary business only, but Mr Byrne’s office in Hodge Hill used 543 of them to keep constituents up to date on developments in an ongoing fight to halt the development of a Tesco store on Brockhurst Playing Fields.

The Cabinet Office minister has now offered to pay back the cash and claimed he was out of the country when the mistake happened.

Mr Byrne said: “This was a genuine mistake made by a trusted volunteer when I was out of the country on business. I believe a volunteer got muddled and did not appreciate the consequences of this mistake. I offer my sincere apologies for this mistake. I will of course repay the cost of the envelopes.”