The Conservative MP for Dover has staged a dramatic defection to Labour saying her former party has become “a byword for incompetence and division”. Natalie Elphicke became the second Tory MP to switch parties in two weeks in another major blow to Rishi Sunak as she crossed the floor of the Commons before prime minister’s questions on Wednesday. In a move that took Westminster by surprise, and went down badly with some Labour MPs owing to her “hard-right views”, Elphicke said the UK needed to move on from Sunak’s “tired and chaotic” government, accusing the prime minister of failing on border security. “Rishi Sunak’s government is failing to keep our borders safe and secure,” she said in a statement. “Lives are being lost in the English Channel while small boat arrivals are once again at record levels. It’s clear they have failed to keep our borders secure and cannot be trusted.” At PMQs, Keir Starmer welcomed her to Labour, asking Sunak “what is the point of this failed government staggering on … [when] the Tory MP for Dover, on the frontline of the small boats crisis, says the prime minister cannot be trusted with our borders?” It was unclear when Sunak first heard about the defection, as a surprised looking Penny Mordaunt, the Commons leader, rushed over talk to him beforehand after spotting Elphicke just behind Starmer on the Labour benches. A Labour source said Elphicke would not be fighting her seat at the next election, and had not been offered a job or a peerage, but could informally advise the party on housing policy. She is understood to have met Starmer once before crossing the floor. Starmer’s spokesperson defended the move, despite the fact Elphicke’s admission to the Labour party will be controversial as a result of some of her previous stances and conduct. “It’s a sign of the progress that we’ve made that people recognise that on some of the key challenges facing the country, the Tories have failed,” he said. “Here is someone who is willing to make the significant step of switching across to Keir Starmer’s changed Labour party and that’s something we’re very happy to see.” Elphicke succeeded her then husband, Charlie Elphicke, as the MP for Dover in 2019 after he was suspended from the Conservative party over sexual assault allegations. He was found guilty two years later. After his conviction, his ex-wife defended him in an interview with the Sun, saying he was “attractive, and attracted to, women” and that had made him “an easy target for dirty politics and false allegations”. Elphicke was one of several Tory MPs who were suspended from the Commons and told to apologise for being found to have tried to influence a judge presiding over his trial. Her comments on migration have repeatedly caused controversy. A year ago she wrote an article for the Daily Express calling Starmer “Sir Softie” and accusing Labour of wanting “open borders”. She wrote: “Not only have Labour got no plan of their own to tackle illegal immigration, they simply do not want to.” She also clashed with the England footballer Marcus Rashford, who she said should have spent more time “perfecting his game” rather than “playing politics” – a reference to his campaign for free school meals – after he missed a penalty at the Euro 2020 final. There was anger among MPs over the defection. A shadow minister ordinarily supportive of Starmer said: “Logically or politically we didn’t need this … I worry that they’ll not have done sufficient due diligence on her.” They added: “Her hard-right views are a big red line too. Are we welcoming Nigel Farage next week?” One Labour MP said there was significant anger among some women in the party. “Most of us on the backbenches struggle to get any contact at all from the Labour leader or his team – perhaps if we were to stand in front of a few more flags or join the [European Research Group]?” An MP on the left of the party added: “I think many in the party think it’s disgusting, that we don’t need people like that in the Labour party, and that she is absolutely vile … Who in their right mind thought this was helpful?” Sunak’s spokesperson said that Elphicke’s defection would “come as a surprise to her constituents, given that they are on the frontline of the illegal immigration issue and she has spent years tweeting about how Labour have absolutely no plan to deal with this”. In a statement,, Elphicke said: “When I was elected in 2019, the Conservative party occupied the centre ground of British politics. The party was about building the future and making the most of the opportunities that lay ahead for our country. “Since then, many things have changed. The elected prime minister was ousted in a coup led by the unelected Rishi Sunak. Under Rishi Sunak, the Conservatives have become a byword for incompetence and division. The centre ground has been abandoned and key pledges of the 2019 manifesto have been ditched. “Meanwhile, the Labour party has changed out of all recognition. Since 2019, it has moved on from Jeremy Corbyn and now, under Keir Starmer, occupies the centre ground of British politics.” Elphicke is the second Tory MP to cross the floor in the past two weeks. On 27 April, the former health minister Dan Poulter defected from the Conservatives to Labour and criticised the government’s record on the NHS. In January 2022 during Boris Johnson’s leadership, the MP for Bury South, Christian Wakeford, defected.