The UK could run out of gas this winter if demand peaks and supplies are hit, the energy regulator warned yesterday.

Ofgem said gas supply resilience has been reduced by falling North Sea reserves and a reduction in imports. It came after Jonathan Brearley, the most senior energy department civil servant, admitted he could not guarantee the lights wouldn’t go out.

Ofgem said: ‘Without intervention, Britain could face a negative supply margin… involving extremely high gas demand on a 1-in-20 cold weather day [a day so cold Britain would only be expected to have one every 20 years] and the loss of the single largest element of gas infrastructure. The position could become more constrained in future.’

Read more: Britain could run out of gas this winter, Ofgem warns