Welfare 31 October 2019 Five things you need to know today: Corbyn launches campaign, and Twitter bans political ads Also: remain campaign group under fire for tactical voting website. Getty Sign UpGet the New Statesman\'s Morning Call email. Sign-up Corbyn launches campaign Jeremy Corbyn is to launch Labour's election campaign with a promise to rebuild public services and attack "the corrupt system" run by "tax dodgers, dodgy landlords, bad bosses and big polluters". In a speech today, the party's leader will also describe the vote as a "once-in-a-generation chance to transform our country". In a fairly clear indication of the terrain on which he wants to fight this election, Boris Johnson has responded by blaming Corbyn for delaying Brexit. Tactical voting sites under fire A tactical voting website launched by the Best for Britain group has come under fire for suggesting that remain voters back the Liberal Democrats in a number of seats where the party cannot win, or where the best chance of defeating the Tories is to vote Labour. The campaign group defended the tool, and said it would continue to add data. But a Labour spokesperson said: “A vote for the Lib Dems in almost every seat in the country helps put Johnson in Downing Street.” More MPs stand down Former Cabinet ministers Nicky Morgan and Amber Rudd have become the latest Tory moderates to confirm they will not be seeking re-election at the upcoming election. Others include Theresa May's former de facto deputy prime minister Sir David Lidington, and the one-time Chancellor and father of the house Ken Clarke. In all, more than 50 MPs have so far confirmed they are standing down. Dozens dead in Pakistan train fire More than 65 people have died on the railway line between the Pakistandi cities of Karachi and Rawalpindi, after the train they were travelling on caught fire. A ministers said that fire was caused by the explosion of a gas cylinder which passengers were using to cook breakfast. Political advertising faces Twitter ban Twitter is to unveil plans to ban all political advertising next month. The company's chief executive Jack Dorsey tweeted yesterday that the power of internet advertising “brings significant risks to politics”, and that the reach of such messages “should be earned, not bought”. Larger rival Facebook recently ruled out doing the same. › Nicky Morgan's resignation shows the real reason so many MPs are stepping down Subscribe For more great writing from our award-winning journalists subscribe for just £1 per month!