Conservative PM Theresa May will claim Labour has “deserted” working-class voters as she campaigns in the north-east of England on Friday.
She will pledge to campaign “in all corners” of the UK to reach those who have been “abandoned by Labour”.
She will say that people have voted Labour for generations but many are “appalled” by Jeremy Corbyn’s beliefs.
Mr Corbyn says the pledges in Labour’s manifesto – a draft of which was leaked on Wednesday – will be “very popular”.
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The leaked draft contains policies on nationalising railways, renewing Trident weapons, abolishing university tuition fees and scrapping the public sector pay cap.
Speaking after his party unanimously approved the final version, which will be officially unveiled next week, Mr Corbyn said it would be “an offer that will transform the lives of many people in our society and ensure that we have a government in Britain on 8 June that will work for the many, not the few”.
A ComRes survey for the Daily Mirror published on Friday suggests Labour’s general election pledges, such as the nationalisation of rail and postal services, are more popular among voters than Mr Corbyn himself.
‘Policies of 1970s’
Mrs May will say her opponent’s programme represents a return to “the disastrous socialist policies of the 1970s”.
“Proud and patriotic working-class people in towns and cities across Britain have not deserted the Labour Party – Jeremy Corbyn has deserted them,” she is expected to say.
“We respect that parents and grandparents taught their children and grandchildren that Labour was a party that shared their values and stood up for their community.
“But across the country today, traditional Labour supporters are increasingly looking at what Jeremy Corbyn believes in and are appalled.”
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She will highlight Conservative policies to cap energy bills, protect workplace pensions and improve mental health provision, while investing in the armed forces.
“I will be reaching out to all those who have been abandoned by Labour and let down by government for too long.
“I will be doing everything I can to earn their trust,” she will say.
“My commitment to them is this: if you put your trust in me, back me, I will strive to be a leader worthy of our great country.”
Leaked reports of Labour’s draft manifesto suggest the party will match the Conservatives’ commitment to spend a minimum of 2% of national income on defence, in line with a Nato target.
The Conservatives insist that despite big cuts to the defence budget between 2010 and 2015, which saw a fall in the size of the army, the UK remains a key player within Nato and on the international stage.
Despite the leaked draft Labour manifesto committing to the renewal of the Trident submarine system, the Conservatives argue Mr Corbyn’s longstanding opposition to the UK’s nuclear weapons capability poses a threat to security.
Theresa May is targeting Labour seats in the north of England which voted Leave in last year’s EU referendum.
She has accused EU officials of trying to interfere in the election after details of a Downing Street dinner appeared in a German newspaper last month.
Brexit Secretary David Davis told the Daily Telegraph on Friday that he believed European Commission president Jean-Claude Juncker and his aides – reported to have been behind the leaks – had “learnt their lesson”.
“He is not going to be meddling in British politics any more – or at least if he does he will get the same reaction.
“All these stories are briefing against me, trying to get me sacked – which, of course, is a compliment by the way,” he said.
The prime minister has said she remains committed to her party’s target of reducing annual net migration to less than 100,000 despite it being repeatedly missed since 2010. She has not said how this will be achieved.
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