Tory MP Steve Baker has called for beleaguered Government chief aide Dominic Cummings to resign.
Mr Baker, a leading member of the influential 1922 Committee, is the first Conservative to have broken ranks over the lockdown row.
There has been a concerted campaign to support Mr Cummings – a close adviser to the Prime Minister Boris Johnson.
The aide is said to have travelled from his London home to stay with his parents 260 miles away during lockdown.
That has been admitted, but a second reported sighting of Mr Cummings in the North East has been dismissed as “totally false”.
Steve Baker MP
Mr Barker, speaking on the Sophy Ridge on Sunday programme, argued the farrago was the “end of the road”.
He said: “If he doesn’t resign, we’ll just keep burning through Boris’ political capital at a rate we can ill afford in the midst of this crisis.
“It is very clear that Dominic travelled when everybody else understood Dominic’s slogans to mean ‘stay at home, protect the NHS and save lives'”.
However, Transport Secretary Grant Shapps defended Mr Cummings.
He said “necessary precautions” were taken while the Cummings’ family was isolating in Durham.
Mr Shapps insisted he “did not return to Durham for a second time”.
