Boris Johnson backer Leadsom opposes proroguing parliament

<span>Photograph: Jonathan Hordle/REX/Shutterstock</span>
Photograph: Jonathan Hordle/REX/Shutterstock

A leading supporter of Boris Johnson has said she would not be willing to stand for him proroguing parliament to push through a no-deal Brexit and does not believe he would take such a step.

Andrea Leadsom, a former leader of the House of Commons, who also stood to be prime minister, said she fully agreed with Johnson that the UK needed to leave the EU on 31 October no matter what. But she rejected the idea parliament could be suspended to achieve a no-deal Brexit, when asked if she could go along with such a plan.

“No I don’t believe I would and I don’t believe it would happen,” she told the BBC Radio 4 Today programme.

Instead, Leadsom endorsed a series of mini-deals on issues such as protecting EU citizens’ rights, even though Brussels had repeatedly said the withdrawal agreement needed to be done as a package and that was the only way of getting a transitional period.

Johnson, the runaway favourite to be prime minister, has hardened his Brexit position since the Tory leadership contest began, refusing to rule out proroguing parliament to push through no deal and declaring Theresa May’s withdrawal agreement and its controversial Irish backstop dead.

He has insisted that the chances of no deal are “a million to one”. Some of his senior Eurosceptic backers told the Guardian that this was “just rhetoric”, adding they believed he would spin existing or potential side deals on specific areas of agreement with the EU as evidence that he was not pursuing a no-deal Brexit.

Related: Laughter and lies: Johnson's journey from journalist to MP

Conservative MPs fighting against a hard Brexit – with the threat of no deal looming and the pound falling on Tuesday – have been organising to make sure parliament is not sidelined. They have also been considering whether they could vote down their own government if necessary, probably triggering an election.

Senior MPs on Johnson’s campaign said they believed he wanted to avoid an election before Brexit at all costs but there would undoubtedly have to be one within the next year in order to govern effectively. Campaign sources told the Times that Johnson wanted to fight an election while the Labour leader, Jeremy Corbyn, was still in post.

The official campaign line is there will be no election until 2022. But many MPs do not believe it would be possible for him to govern with a minuscule working majority of just three or four, even if he retained the support of the Democratic Unionist party.