The ex-PM saw in advance a report by the Commons Privileges Committee investigating if he misled the Commons over Downing Street lockdown parties, reports BBC.
In his statement, Johnson described the Committee as a 'kangaroo court'.
He said its purpose 'has been to find me guilty, regardless of the facts'.
The cross-party committee of MPs - with a majority of Conservatives - added it would conclude its inquiry on Monday and 'publish its report promptly', reports BBC.
Following his resignation, there will be an by-election in his constituency of Uxbridge and South Ruislip.
He had served as the PM of the country from July 2019 until September 2022.