Dominic Cummings has claimed that multiple witnesses "would swear under oath" that the Prime Minister "lied to Parliament" over a Downing Street party.
In his blog, the former aide said he personally raised the "drinks party" with Boris Johnson and called No10 a "madhouse" but said the Prime Minister "waved it aside".
It comes after the Prime Minister told MPs he "believed implicitly" that a BYOB bash on May 20 2020 was a work event, the Mirror reports.