British MPs have decided to open an investigation targeting Boris Johnson over the so-called "partygate" scandal, to find out whether he knowingly misled Parliament about illegal social events held on government property during coronavirus lockdowns. The move will be seen as a major test of trust in the prime minister, and if the inquiry finds that he lied, the pressure will only grow for him to respond in the traditional manner and resign. It follows a police fine Johnson received last week for attending a birthday celebration in his office in June 2020 in violation of lockdown rules. An investigation was approved by parliamentarians without a formal vote due to the lack of opposition, and will now be carried out by Parliament’s Committee of Privileges. This happened despite the Conservative majority in parliament, as many ruling party lawmakers are uneasy about Johnson"s behaviour. The government abandoned efforts to block the move by the Labour opposition to instigate the probe. The move sought to uphold “the simple principle that honesty, integrity and telling the truth matter in our politics,” Labour leader Keir Starmer said. “But it is a principle under attack.” The prime minister"s grip on power has been shaken by claims he flouted the pandemic rules he imposed on the country, then repeatedly failed to own up to it. Johnson was fined £50 (€60) for attending his own birthday party in his office, when people in Britain were barred from meeting up with friends and family, or even visiting dying relatives. He is the first British prime minister ever found to have broken the law while in office. Johnson denied he knowingly broke the rules, but his shifting responses have drawn derision and outrage from opponents. The prime minister"s fate rests with the views of MPs on his own side. For the time being, the war in Ukraine has prevented critics from moving against Johnson at a time of international crisis -- but that may change after local elections in May if the Conservatives perform badly. One veteran government backbencher, Steve Baker, who had backed Johnson until now, turned against him on Thursday, calling in parliament for him to go. "The prime minister should just know the gig"s up," he said. The Committee of Privileges probe will not start until twin police and civil-service investigations into “partygate” have concluded. Boris Johnson was not present for the decision; he is in India on a two-day visit focused on boosting economic ties with the country. The prime minister again denied knowingly misleading Parliament and insisted he would lead the Conservatives into the next national election, due in 2024. “I have absolutely nothing, frankly, to hide,” he told Sky News from the western state of Gujarat. “I want to get on with the job that I was elected to do.” — Euronews