A Government website claiming it takes just five minutes more to drive from Weston-super-Mare to Bristol in rush hour than at other times, has been branded ridiculous by the town's MP.

According to the Government's transport information site, the journey time from the seaside town to Bristol is only five minutes more during peak hours than it would be during quieter times of the day.

The website was used as part of a review into the future of 50 jobs at the town's tax office. The Government argued the journey time was acceptable enough to transfer the jobs from the town to Bristol.

Tory MP John Penrose said the review was flawed because the journey time at rush hour was up to half an hour longer.

HM Revenues and Customs announced in June it was planning to reduce its South West branches from 34 to 21.

It said the move was part of an ongoing strategy to reduce costs across the UK and carried out an eight-week consultation, which has ended.

The full results have not yet been announced.

Mr Penrose has written to the Government concerned about the accuracy of the information on its transport site. The website is being used by the Government to work out journey times for staff if relocated from Weston.

Despite the five-minute difference between peak and off-peak travel times cited on the website, Mr Penrose says most people would allow an extra 20 to 30 minutes at rush hour, due to the problems around Junction 21 of the M5.

The chief executive of Transport Direct, a subset of the Department for Transport, Nick Illsey confirmed the website could calculate journey times on motorways quite accurately, but not for the roads people use to get onto the M5 at J21. His reply letter to Mr Penrose states that the website "does not have accurate measurements for factors such as peak-hour delays at J21 accessing the M5".

Mr Penrose said: "To claim that it only takes five minutes extra to get to Bristol from Weston at peak time is absolutely ridiculous.

"As anyone who's sat in the queue and resultant chaos at Junction 21 in the morning will tell you, it takes a frustrating 20 minutes to get through and onto the M5 and sometimes even longer."

This proved a key part of the Government's case for closing the Weston tax office is seriously flawed, because they're seriously underestimating the time it will take for staff to commute into Bristol".

He added: "This just strengthens the case for improvements to J21 and bringing more jobs to Weston-super-Mare before we build any more houses."