Kemi Badenoch is facing open criticism from her Tory leadership rivals this afternoon, despite election rules forbidding blue-on-blue attacks.

The frontrunner among the party membership told Times Radio this morning that maternity leave is now “excessive” and causing a strain on businesses with red tape.

The firebrand candidate said: “Maternity pay varies, depending on who you work for. But statutory maternity pay is a function of tax, tax comes from people who are working. We’re taking from one group of people and giving to another. This, in my view, is excessive.”

“Businesses are closing, businesses are not starting in the UK, because they say that the burden of regulation is too high.”

Asked if she thought maternity pay is excessive, she replied: “I think it’s gone too far the other way, in terms of general business regulation.”

The comments have sparked consternation among rival camps and their supporters, who are concerned Ms Badenoch’s reputation for grabbing attention could prove a headache in opposition.

This afternoon her main rival Robert Jenrick criticised the comments, telling a conference fringe: “I don’t agree with Kemi on this one”.

He added: “I’m a Father of 3 young daughters I want to see them get the support they need when they enter the workplace.

“The Conservative party must be on the side of working mothers.”

The former immigration minister also pointed out that maternity pay is already among the lowest of any country in the OECD, though said he believes it should remain at its current level.

Tom Tugendhat also hit back against Ms Badenoch, arguing it is “incredibly important that women have the ability to choose how to live their lives”.

“It’s not for me to tell you whether you should go to work or stay at home or which job to do, or how many kids to have. That’s none of my business. What’s my business as a politician is to make sure that you have the support for choice.”

When asked about the comments, James Cleverly, the fourth leadership contender, simply replied “You need to ask Kemi about Kemi's comments”, with the Express understanding he does disagree with them.

Ms Badenoch has now accused her rivals of instigating a “pile on” against her, but sources insist she is not worried about the furore.

A source in her leadership camp told the Express: “Infighting and internal conflicts helped take our party to an historic defeat. We need to be better, we need our politics to be better.”

“Kemi obviously supports maternity pay and was making a case for lower regulation - something she always aimed for as business secretary.

“For other leadership campaigns to be seeking to use selective quotes from an interview to score political hits, shows they’re still wedded to the old politics and simply aren’t serious about getting back to government.”

Mr Jenrick also levelled further criticism at Ms Badenoch during a fringe event this afternoon, arguing that her propensity to push policy arguments away and say she’ll conduct them after the election has concluded.

He argued that this approach would be a “recipe for disunity”, adding that this week’s conference should be used as a “crucible of debate” which will allow the next leader to get cracking on their policy programme straight away.