Tory frontrunner says reports of an effort to keep sensitive information from him as foreign secretary are untrue

Boris Johnson has hit out at claims that Downing Street sought to restrict his access to some sensitive intelligence information when he became foreign secretary in mid-2016.

The Conservative leadership frontrunner told a hustings of party members that “he was extremely dubious about the provenance” of the story that had led the BBC morning bulletins and that it was untrue.

Rumours have circulated in political and intelligence circles that Johnson’s access to intelligence briefings was restricted during his time as foreign secretary, an interesting claim given that the role includes responsibility for MI6 and GCHQ.

The BBC report said that in 2016 Downing Street did not want Johnson to be shown a category of sensitive secret intelligence. One source said this was down to “control freakery” on the part of No 10 rather than fears about whether Johnson could be trusted.

Johnson’s campaign team has obtained assurances from Downing Street insiders from the time, who insisted there was no attempt to prevent him from seeing relevant intelligence.

Downing Street in the early period of Theresa May’s tenure was run by two joint chiefs of staff, Fiona Hill and Nick Timothy. People who worked for them at the time told the Guardian they were “obsessed by controlling information”, but they had no specific evidence that Johnson was singled out to be cut out of intelligence briefings.

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

At the same hustings, Johnson’s rival for the leadership and the current foreign secretary, Jeremy Hunt, said there was a rule that ministers had to remain tight-lipped on intelligence matters.

“We have the finest intelligence services in the world in this country – that does depend on some discretion by the foreign secretary so I’m not going to breach that now,” Hunt said.

Britain’s intelligence agencies are normally wary of becoming embroiled in any kind of political debate or dispute, and even raising the question has caused nervousness in the intelligence community.

Whitehall sources said ministers received briefings or information that was appropriate to their role in government, and that general procedure was followed in Johnson’s case.

It would be normal for a prime minister to have more information than their senior prime ministers, as only Downing Street would have the full set of available information at any one time.

Sources close to Johnson say there was no row at the time about being denied access and added that he saw everything he should have seen as foreign secretary.

The prime minister’s spokesperson said on Friday: “We don’t comment on intelligence matters.” Asked whether May had trusted Johnson at the time, she said yes.

The spokesperson added: “It’s a matter of fact that it was the PM’s decision to appoint Boris Johnson as FS in full knowledge of all the responsibilities that that involves. He did a good job as foreign secretary in his time in the post.”