Boris Johnson has claimed there is nothing "remotely dodgy" about contact between him and billionaire industrialist James Dyson, as he prepares to release details of their conversations.
The prime minister confirmed he would publish messages later on Friday in an attempt to cool a lobbying row over unofficial contact between the pair over tax.
Sir James, a prominent business ally of Mr Johnson, had asked the prime minister to personally "fix" an issue with the tax status of Dyson staff working in the UK on ventilators, according to leaked messages that have sparked a Downing Street inquiry.
Labour says the revelations about Mr Johnson's contact with the vacuum cleaner manufacturer are part of a pattern of government "sleaze" and cronyism that extends to other Covid contracts.
Speaking on a visit to a farm in Stoney Middleton, Derbyshire, on Friday, Mr Johnson said the release of the messages was "happening today".
But he added: "Let me tell you, if you think that there's anything remotely dodgy, or rum, or weird or sleazy about trying to secure more ventilators at a time of a national pandemic and doing everything in your power to do that then I think you're out of your mind."
Downing Street has briefed Conservative-supporting newspapers that the messages could have been leaked by former advisor Dominic Cummings, who has not yet commented on the matter.
Sir James has been a staunch supporter of Brexit, though his company has since announced it will be moving its head office to Singapore.
Minister Caroline Dinenage took to the airwaves earlier in the day to defend her boss Mr Johnson, claiming her colleagues do similar things "all the time".
"We don't hand out our mobile numbers willy-nilly but government ministers do have to engage with businesses all the time," Ms Dinenage, the digital minister told Times Radio.
"We engage with charities all the time, we engage with unions all the time.
"The key thing is that we follow the process, we pass anything like that on to the civil service team to take forward. There are very clear rules and that's what we all do.”
