UK's embattled Prime Minister Boris Johnson will face a vote of confidence in his leadership of the Conservative Party, the chair of the party's backbench committee announced on Monday, days after more details of the partygate scandal emerged.

Sir Graham Brady, who is in-charge of collating the letters of no-confidence received by the 1922 Committee, said the threshold of 15 per cent of the Tory parliamentary party, or 54 MPs, seeking such a vote has been met and it will place on Monday evening in the House of Commons. "The threshold of 15 per cent of the parliamentary party seeking a vote of confidence in the leader of the Conservative Party has been exceeded," Brady said in a statement. "In accordance with the rules, a ballot will be held between 18:00 and 20:00 (local time) today Monday June 6, details to be confirmed. The votes will be counted immediately afterwards. An announcement will be made at a time to be advised. Arrangements for the anno will be released later today," he said.