Tory backbencher Bob Blackman faces repaying more than £1,000 in wrongly-claimed mileage expenses.

An investigation by the Independent Parliamentary Standards Authority (Ipsa) has found that the Harrow East MP, who lives in Wembley, submitted more than 700 “inaccurate” claims.

The Ipsa inquiry’s provisional findings state: “The Compliance Officer has concluded that mileage claims submitted by Mr Blackman are, in almost every instance, not accurate and greater than the distance travelled. This is disputed by Mr Blackman.”

Compliance Officer Peter Davis found that Mr Blackman, a former Brent councillor, wrongly submitted claims for travelling from his constituency home in Wembley to his office, and for going to party political events and canvassing sessions.

The report also revealed that Ipsa has been warning him about high mileage claims since 2011.

n October that year officials wrote to him voicing concern that he was putting in for “around twice the average for constituency mileage across the UK and some six times higher than other suburban London area constituencies where mileage is claimed”.

Ipsa bosses requested an initial investigation by the compliance officer in December 2012, saying he appeared to be hugely over-estimating distances and rounding them to the nearest five miles.

A two-mile journey to Harrow Weald had been claimed as 10 miles.

However, after a discussion with Mr Blackman, Mr Davis declined to open a formal investigation, instead deciding the issue could be dealt with through “support and advice from Ipsa to ensure the MP improved his record-keeping”.

But an audit in 2013-14 found that Mr Blackman had again racked up the highest mileage of any MP.

In a statement, Mr Blackman, who is also a former depury leader of accused Mr Davis of enforcing “rules that he believes should exist” and insisted he did not accept the finding.

The MP said: “There was a single incorrect claim, where the amount entered was wrong, which was an isolated error.

“I supplied detailed maps for the routes that I routinely took which the Compliance Officer ignored.

“Therefore, all claims for seven miles have been adjusted to six miles around the constituency which created a repayment.

“Subsequently, since my trip computer continues to record the exact same mileage as previously claimed, I am concerned that the Compliance Officer is not interpreting rules that exist but rules that he believes should exist.

“On that basis, I do not accept the provisional findings. As such, I have invited him to publish a revision of the rules containing this or to apply the same level of scrutiny to all 650 MPs’ mileage claims.”

Mr Blackman has 15 days to appeal.