In a scathing speech directly challenging the Prime Minister's approach to truth and the 'partygate' saga, Sir John said the Government had looked “distinctly shifty” in its approach.
Sir John, a former Conservative Party leader, argued that the UK’s reputation overseas was being “shredded”, undermining its attempts to influence world affairs. Mr Johnson is in Brussels today.
Sir John also indicated that Mr Johnson should resign if he deliberately misled Parliament over 'partygate', saying that convention “must always” be followed.