Jeremy Corbyn insisted today that Labour was increasingly united on the big issues, even as a showdown meeting with party critics looms.

The Labour leader – who is expected to be re-elected by a big margin next weekend – pointed to opposition to further spending cuts and new grammar schools as policies that are bringing the party together.

Tomorrow, Mr Corbyn and his deputy, Tom Watson, will go head-to-head at a crucial meeting of the party’s ruling National Executive Committee (NEC), over rival plans for electing the Shadow Cabinet.

Meanwhile, centrist Labour MPs fear that Mr Corbyn’s allies will try to force their deselection by local constituency parties – a move threatened by Unite union leader Len McCluskey yesterday.

But Mr Corbyn, asked about his rebellious MPs, said: “Of course I’m going to reach out to them as I have reached out to them in the past”.

He said they needed to understand the “honour and responsibility” of being a Labour MP, with a booming party membership behind them, expecting unity.

And he added: “It doesn’t mean that everybody agrees on everything all the time – that I understand.

“But the general direction of opposition to austerity, opposing the Tories on grammar schools – those are the kind of things that actually unite the party these days.”

Mr Corbyn also sought to stamp on suggestions that he would stand down if general election defeat appeared inevitable, saying: “We are here to win an election – I’m determined to do that election.”

Labour leadership contest: Jeremy Corbyn vs Owen Smith Show all 8 1 /8 Labour leadership contest: Jeremy Corbyn vs Owen Smith Labour leadership contest: Jeremy Corbyn vs Owen Smith Jeremy Corbyn and Owen Smith clash at a leadership hustings in Gateshead, where Mr Smith was scarcely able to answer a question without being booed by Mr Corbyn’s supporters PA Labour leadership contest: Jeremy Corbyn vs Owen Smith “Jeremy himself admitted he was seven out of 10 in terms of his faith in the European Union. He said it,” said Mr Smith during his second live debate with Jeremy Corbyn Getty Labour leadership contest: Jeremy Corbyn vs Owen Smith Ballot papers are currently due to be sent out on 22 August and returned a month later, with the result being announced at a special Labour conference on 24 September Getty Labour leadership contest: Jeremy Corbyn vs Owen Smith Jeremy Corbyn supporters cheer and wave placards as the Labour Leader addresses thousands of supporters in in Liverpool, England Getty Labour leadership contest: Jeremy Corbyn vs Owen Smith Labour Party leadership candidate Owen Smith poses for a picture with supporters during a picnic for young members in London Fields, Hackney in London Getty Labour leadership contest: Jeremy Corbyn vs Owen Smith The Labour leader has a spring in his step at a leadership rally in Sunderland Screenshot Labour leadership contest: Jeremy Corbyn vs Owen Smith Labour leadership contender Owen Smith delivers a speech at the Open University in Milton Keynes, where he promised to reverse Conservative cuts set to leave millions of low paid workers thousands of pounds a year worse off PA Labour leadership contest: Jeremy Corbyn vs Owen Smith Shadow Chancellor John McDonnell has urged Owen Smith to distance himself from those saying they want to split the Labour party Getty

The leader was interviewed by BBC Radio’s Today programme after the last of dozens of packed leadership campaign rallies – attended by “tens of thousands of people”, he said.

Mr Corbyn pointed to that “strength in numbers”, arguing it would form a “very strong campaigning base for the Labour movement” – particularly in areas where it had been dormant.

He said: “I think you will begin to see that play out, particularly in the local elections next year and after that”.

Jeremy Corbyn dons the gloves during a visit to The Big Spar at the Caris Boxing Club for Young Homeless People (Rex)

But the comments are unlikely to satisfy many of the 172 Labour MPs who passed a vote of no confidence in their leader in the summer and fear he is leading them to certain election disaster.

Some big names are expected to return to the front bench if Mr Corbyn wins again, particularly if the party some embraces elections to at least some Shadow Cabinet posts.

However, others speak of a long “war of attrition”, an effort to present the centrists almost as a “party within a party”, attract more moderate members – and further attempts to topple Mr Corbyn.

Today, one former Labour shadow minister, Neil Coyle said Jeremy Corbyn and deputy leader, John McDonnell, were “failing abysmally” to reach out to disaffected MPs.

It emerged yesterday that the future of Mr Watson and Labour’s general secretary, Iain McNicol, was discussed at a summit of Mr Corbyn and his closest allies three weeks ago.