In an email to customers, Greggs said: “Just to let you know – the following shops will be temporarily closed on Wednesday 24th and Thursday 25th June to protect our customers and colleagues during the severe hot weather.” The list includes two outlets in London - one in Barnet and another in Leicester Square. The others on the list are Wantage, Aldridge, Wolverhampton, Luton, Trowbridge, Marlborough, Dudley and Northampton.

It comes as the Met Office issued a Red warning for extreme eat for Friday. The first time in the history of the current weather warnings system that red warnings have been issued for extreme heat for three consecutive days in the UK.

Andy Page, a Met Office Chief Meteorologist said: “This exceptional spell of hot and humid weather will maintain its grip on the UK for a little longer.

"Although the current red warning for areas in more central and western parts of England and Wales will expire later today, the heatwave will still be bringing high temperatures to these areas, albeit moving away from the peak heat of Wednesday and Thursday.

"We are expecting that some daytime maximum temperatures could exceed 36C, perhaps rising to 37C in some locations.”