Tory leadership contender says English is not first language in ‘too many parts of our country’

Boris Johnson has said there are “too many parts of our country” where English is not spoken as a first language and that he would require all immigrants to Britain to learn English.

At a hustings event for the Conservative leadership race in Darlington on Friday, the former mayor of London praised the capital’s diversity but suggested some communities were not doing enough to integrate into society.

“Now I think that the story of communities that have come to London and made their lives in London is amazing … waves have come to London and slowly they have changed, they have adapted, they have made their lives, and they’ve helped to make our national culture and they’ve bought into it. And that’s what I want for our country,” he said.

“I want everybody who comes here and makes their lives here to be, and to feel, British – that’s the most important thing – and to learn English. And too often there are parts of our country, parts of London and other cities as well, where English is not spoken by some people as their first language and that needs to be changed.

“People need to be allowed to take part in the economy and in society in the way that that shared experience would allow.”

Johnson later went on to visit Scotland, where he refused to rule out blocking a second referendum on Scottish independence, even if the Scottish National party won a mandate for one at the next Holyrood elections.He maintained that “we should stick to that promise” that the 2014 vote was decisive for a generation.

Johnson and his leadership rival, Jeremy Hunt, arrived in Darlington before the most important weekend in the race to be the next prime minister – ballot papers drop through members’ letterboxes over the next 24 hours.

Quick guide Tory party leadership contest Show Hide What happens next in the Tory party leadership race? As she announced on 24 May, Theresa May stepped down formally as Conservative leader on Friday 7 June, although she remains in place as prime minister until her successor is chosen. In a Conservative leadership contest MPs hold a series of votes, in order to narrow down the initially crowded field to two leadership hopefuls, who go to a postal ballot of members.

How does the voting work? MPs choose one candidate, in a secret ballot held in a committee room in the House of Commons. The votes are tallied and the results announced on the same day. In the first round any candidate who won the support of less than 17 MPs was eliminated. In the second round anybody reaching less than 33 votes was eliminated. In subsequent rounds the bottom placed contender drops out until there are only two left. The party membership then chooses between them. When will the results be announced?

The postal ballot of members has begun, and the Tory party says it will announce the new prime minister on 23 July.. Photograph: Neil Hall/EPA

Activists wearing “Back Boris” T-shirts canvassed party members in the foyer of Darlington’s Edwardian-era Hippodrome theatre, the venue for the eighth of 16 hustings taking place across Britain.

Profile Boris Johnson's Tory leadership campaign Show Hide Personal style A late-night altercation between Tory leadership favourite, Boris Johnson, and his partner, Carrie Symonds initially changed the dynamics of Johnson's campaign. He had been either invisible or deliberately sober to the point of dullness, when his usual primary draw to Tory members is a self-created sense of optimism and fun. Much is also made of his supposed broad appeal to the electorate, evidenced by two terms as London mayor. His bizarre claim to make model cardboard buses has raised eyebrows. In most political contests, Johnson’s character – he has lost more than one job for lying, and has a complex and opaque personal life – would be a big issue, but among the Tory faithful he seemingly receives a free pass. It remains to be seen what impact that late-night police visit will have on his chances. Brexit He has promised to push for a new deal while insisting the UK will leave the EU come what may on 31 October, even if it involves no deal. While his hard Brexit supporters are adamant this is a cast-iron guarantee of leaving on that date, elsewhere Johnson has been somewhat less definitive. Asked about the date in a BBC TV debate, Johnson said only that it was 'eminently feasible', although he then went on to tell TalkRadio that the 31 October deadline was 'do or die'. Taxation His main pledge has been to raise the threshold for the 40% higher tax rate from £50,000 to £80,000, at a cost of almost £10bn a year, which would help about 3 million higher earners, a demographic with a fairly sizeable crossover into Tory members. Johnson’s camp insist it would be part of a wider – and so far unknown – package of tax changes. Public spending He has said relatively little, beyond promising a fairly small increase in schools funding, as well as talking about the need to roll out fast broadband across the country. Johnson has generally hinted he would loosen the purse strings, but given his prior fondness for big-ticket projects – London’s cancelled garden bridge, the mooted 'Boris island' airport – perhaps expect more of a focus on infrastructure projects than services. Climate and environment This is unlikely to be a big issue for Conservative party members, and Johnson has not said much on this beyond confirming his general support for the new government target of cutting greenhouse gas emissions to a net zero by 2050. Foreign policy Also unlikely to be a big issue among Tory members, beyond vague platitudes on 'global Britain', it could be a weak spot for Johnson given his poor performance as foreign secretary. He was seen as something of a joke by diplomats – both UK and foreign – and is likely to face more questioning over his gaffe about the jailed British-Iranian woman Nazanin Zaghari-Ratcliffe Peter Walker Political correspondent Photograph: Isabel Infantes/AFP

The former foreign secretary, who has made a series of lavish spending commitments as part of his campaign, told supporters in the north-east he “never liked” the austerity programme of swingeing cuts imposed by his colleagues in government, David Cameron and George Osborne.

“It was always right to reduce the national debt and I pledge as prime minister to continue to reduce the national debt – that is very, very important,” said Johnson, who was London mayor for the first six years of Cameron’s premiership.

“But now is the time, and I believe there’s widespread support for this, that we should do some targeted spending on things that really need investment.”

Hunt was also asked about the austerity cuts and said they had “gone too far” on police budgets and social care. The foreign secretary said he believed Cameron and Osborne “did a superb job” in putting the economy “back on its feet”.

But he added: “I defend what happened then, but with the benefit of hindsight – and it is only with the benefit of hindsight – I think there were a couple of areas where austerity did go too far.

“One of them was on police numbers … and the other is the social care system.”

Profile Jeremy Hunt's Tory leadership campaign Show Hide Personal style His style is notably technocratic, with few rhetorical flourishes and an emphasis on his consensual approach and long record as a minister, notably during more than five years as health secretary, a traditional graveyard of ministerial careers. Hunt’s attempts to talk up a backstory as an 'underestimated' entrepreneur can fall flat given he is also the son of an admiral and was head boy at Charterhouse. Overall, Hunt’s approach can seem uninspiring and hard to pin down in terms of core beliefs, hence the 'Theresa in trousers' nickname among some Tory MPs. Hunt has made headlines by promising to repeal the ban on fox hunting, while always facing scrutiny on his views on the availability of abortion. His campaign team have decided to take the fight directly to rival Boris Johnson though, with Hunt taking part in a Twitter Q&A session as a direct response to Johnson's refusal to appear on a Sky TV head-to-head debate. The hashtag: #BoJoNoShow. Brexit He says a new deal with the EU is possible by 31 October and he would send a cross-party negotiating team to Brussels, including members of the DUP. He would countenance leaving the EU without a deal but is notably more wary than rival Boris Johnson. Taxation Has been fairly silent on this, beyond a proposal to cut corporation tax from 19% to 12.5%, which according to the IFS would cost an estimated £13bn a year. Even at 19%, the UK rate is well below European and global averages. Public spending Before the campaign began he called for a doubling of defence spending, but he has since pulled back slightly, saying only that it should increase. He has argued that cuts to social care budgets had gone too far. Climate and environment Hunt backs the 2050 target for zero net carbon emissions and has called for 'sensible tax incentives' to encourage green initiatives, but very little beyond this. Foreign policy A likely strength for him, as he has been seen as a solid foreign secretary, an impression burnished by taking over from the chaotic Johnson. This has been a key part of his pitch. Peter Walker Political correspondent Photograph: Luke Dray/Getty Images Europe

Hunt gave his “unequivocal” support to HS2, the £5bn high-speed rail link, and Northern Powerhouse Rail, the proposed east-west rail line. Johnson gave his backing to the latter project but avoided a commitment on HS2, having already commissioned a review into its future.

Later on Friday Johnson visited BAE Systems in Govan, on Glasgow’s Southside, before he and Hunt attended Scotland’s only Conservative leadership hustings in Perth that evening.

Speaking to the media after a tour of the shipyard, Johnson said: “I don’t think there’s any need to see any more referendum on [Scottish independence] for this generation. [People] were assured that their votes were decisive, they were told that this was a once-in-a-generation thing and I think we should stick to that principle.”

Johnson also insisted that the union “must come first” if there was a tension between delivering Brexit and the unity of the UK, insisting: “Far from weakening the union a good sensible Brexit will spike the guns of the the SNP.”

Speaking at the hustings event in Perth later, Hunt definitively ruled out agreeing to a second referendum on independence. He won the first cheers of the evening when he told the audience: “If the first minister of Scotland asks me for another independence referendum, I will muster up my British politeness and I will say ‘No’.”

Scottish Conservative critics of Johnson have suggested that his election to Tory leadership could be a “catastrophe” for the UK.

His relationship with Scottish Conservative leader Ruth Davidson, who has backed the foreign secretary Jeremy Hunt, after initially backing Sajid Javid and then Michael Gove, has come under strain. Davidson has regularly called out Johnson’s disruptive behaviour over Brexit and blocked him from attending the Scottish Conservative party conference in Aberdeen in May.

Earlier on Friday, in an interview with BBC Scotland, Davidson held back from saying that she would give Johnson her full support, saying that she would “expect to work with him in a professional manner ... for the good of Scotland”.

• This article was amended on 8 July 2019. An earlier version misnamed the Scottish National party as the “Scottish Nationalist party”.