A group of free-marketeer Brexit backers are hoping to deliver more than 200,000 leaflets across the UK in a bid to prevent Tony Blair from "hijacking" Britain's split from the EU.

The Stop Tony Blair campaign has been launched by Better Off Out, which is run by the libertarian Freedom Association. Rory Broomfield, a director of both organisations, is hoping to raise at least £50,000 to fund the campaign.

"This is only the initial target though. I recognise that we are up against numerous foundations and organisations run by Blair, [George] Osborne, etc, with their many millions, and will need to dig deep in the months to come. With more money we will be able to do more," he said.

The campaign will also see the launch of a new email service, Brexit at Noon, which will be "jam-packed full of useful information about how negotiations are progressing, the EU itself and the opportunities that we face in the wider world".

Blair, one of Labour's most successful leaders and prime minister between 1997 and 2007, campaigned for Remain at the EU referendum. He has since claimed that it is "absolutely necessary" that the UK's split from the EU, expected in 2019, is stopped.

"I think it's possible now that Brexit doesn't happen," he told Sky News in July. "I think it's absolutely necessary that it doesn't happen because I think every day is bringing us fresh evidence that it's doing us damage economically, certainly doing us damage politically."

But despite losing her majority of Conservative MPs in the House of Commons at the general election, Theresa May has pressed on with her plans to break from Brussels, with early talks between Brexit Secretary David Davis and the EU's chief negotiator Michel Barnier concentrating on citizens' residency rights.

Elsewhere, the UK government announced on Thursday that it has commissioned a group of top economists to investigate the financial benefits of migration from the EU.

The independent Migration Advisory Committee (MAC), chaired by Professor Alan Manning, will make a "detailed assessment" of the issue as the two-year-long Brexit negotiations between the UK and the EU continue.

"This is an important and extensive commission and the MAC welcome the opportunity to contribute to the UK's knowledge base in this area at this critical time," Manning said.

"The MAC will research and analyse the areas covered by the questions using all available data sources, using both internal and external analysts and expertise.

"We are keen to work with stakeholders to explore the issues encompassed by this commission and will shortly produce a call for evidence setting out how stakeholders can get involved." The government has set a deadline of September 2018 to report back on the commission.