The government’s new high streets minister has acknowledged that there has to be “fundamental reform of business rates” as retail leaders this week claimed to have won a widespread consensus within and outside parliament.

Penny Mordaunt MP told the Inside Government conference of the future of the high street that she was convinced there needed to be a fully-fledged rethink of rates, rather than simply reform of the administration, as the government has until now insisted on.

This week, more than 100 businesses, including all the major supermarkets, wrote an open letter to the Daily Telegraph, called for a new system which would “unleash investment” and create jobs.

At the BRC annual ­dinner this week, BRC chairman and B&Q CEO Ian Cheshire said he was confident the government would act on business rates after the 2015 election.

BRC director general Helen Dickinson told the event: “We have reached a widespread consensus of the need for major rates reform.

“It’s difficult, it’s complicated but it’s doable, so we will continue and our next step is to get commitment from all the political parties in advance of the next election.”

In July, the BRC shelved its proposals for alternatives to the business rates system, including a radical plan for a new energy tax, after admitting it was too soon to be suggesting new formats for a replacement to the system that brings in £25bn a year to the Treasury, though it claimed 80% of MPs believed the system was “not fit for purpose.”

However, this week Paul Turner-Mitchell, an adviser to the Grimsey Review, claimed the BRC’s decision to accept the 2013 2% cap on rates until after the election would in effect mean approving a £447m rise next year for rates. Labour has said it would reverse any hike in annual business rates due next April and freeze them the following year.