downing street has said boris johnson will fight any challenge to his leadership of the conservative party. it follows a fiery day in the commons over the so—called partygate scandal, with one new mp defecting to the labour party, and a former cabinet minister calling for the prime minister to stand down. nick eardley reports. calm? there isn't much of it around here. westminster is tense about a report into what parties happened in downing street during lockdown, and how long borisjohnson will remain prime minister. yesterday, one conservative mp decided he'd had enough. christian wakeford joined the labour party, very publicly defecting on the floor of the house of commons. music to the ears of his new leader. can i start by warmly welcoming the honourable member for bury south to his new place in the house... cheering. ..and to the parliamentary labour party? mr speaker, like so many people up