Jeremy Corbyn has told supporters that he would challenge the Government “all the way” over Europe.
The Labour leader also said the answer to the country’s problems was socialism during a speech in Liverpool.
Speaking at a raucous party rally on Saturday night, Mr Corbyn said his party would reject Prime Minister Boris Johnson’s deal with the EU as he mobilised for a general election.
Mr Corbyn said: “And he came with his plan, well we’ve got answers to his plan for our relationship to Europe because that plan was all about thumping our workers’ rights, taking away consumer protections, damaging our environment, damaging the Good Friday Agreement.
“But the real purpose behind it is, what they want for the future, which is, as I said in my speech today, is what he’s done today, if he succeeds is fire the starting gun in a race to the bottom.
“We will challenge them all the way, in Parliament next week, we challenge them in crashing out of the EU and we as a movement will come together, those that voted leave or remain have all got a place in the Labour Party and the labour movement.
“What unites us is our determination for socialism.”
Mr Corbyn, who travelled up to Liverpool from the vote on the Government’s EU deal in Parliament earlier today, was interrupted regularly during his speech with chants of “Oh Jeremy Corbyn!” by the crowd, numbering a few hundred strong.
He was cheered and applauded by supporters as he spoke about the Iraq war, arms sales to Saudia Arabia and austerity.
Mr Corbyn said Labour was committed to nationalising, “mail, rail, water and the National Grid” – and promised decent housing and schools and an end to prescription charges.
He also said the rich had got richer and the poor, poorer – and there would be tax rises for the wealthiest 5% of the population.
Mr Corbyn said: “Surely to goodness in the fifth richest country in the world, we can offer our young people something better than a future where they are told they will be poorer than their parents’ generation and they must make their provision for health, for housing for education for pensions and everything else.
“Well, we’ve got a different answer to that and the answer is in a short word, it’s called socialism.”
Mr Corbyn told supporters to get themselves to marginal constituencies to campaign so the party is “up and raring to go” when the election is called.
He added: “This will be an election campaign like no other.
“And I’ll tell you what, one thing I’m very, very certain about, is that nobody but nobody, but nobody will be able to say in the general election of 2019, 2020 whenever it’s going to be, ‘There wasn’t a choice’.
“Oh yes, there will be a choice.
“I am utterly determined, utterly determined that we are ready for an election and to win an election.”
Outside, the Liberal Democrats claimed to have “gatecrashed” the event – with a van circling the venue with a mobile electronic billboard carrying the slogan: “You can’t stop Tory Brexit with Labour Brexit. Only Lib Dems will stop Brexit.”
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