The group contains 59 members of the European Research Group (ERG), a little-known organisation led by High Wycombe MP Steve Baker.
Among the members are leading Eurosceptics Iain Duncan Smith, Dominic Raab, Owen Paterson and Theresa Villiers.
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But while the names are instantly recognisable, the allegedly inordinate influence the group has on Government policy is one of the organisation’s better-kept secrets.
According to reports, the ERG coordinates political strategy through a WhatsApp group entitled: “ERG DExEU/DIT Suppt Group”.
The name is believed to relate to the two Brexit ministries – the Department for Exiting the EU and the Department for International Trade.
Iain Duncan Smith, Dominic Raab, Michael Gove and Theresa Villiers are members of the group.
The goal of the organisation is reportedly to ensure a hard, clean Brexit with no payments to the EU, no reliance on EU courts and maximum flexibility to deal with the rest of the world.
One member told the Times: “Our real power is that, by using the WhatsApp group, we can also ask everyone to shut up.
“If the request goes out, MPs of all levels of seniority stop giving interviews, quotes to newspapers or complaining.
Mr Duncan Smith's criticisms of the High Court judges were reportedly coordinated by the group.
“Sometimes No 10 asks this – the fact we can deliver gives awesome leverage.”
The group holds regular Monday meetings and each MP pays £2,000 a year from their parliamentary expenses towards a full-time researcher and other help.
Among the group’s alleged political interventions are the criticisms led by Mr Duncan Smith of the High Court judges who forced Theresa May to draw up a bill on triggering Article 50.
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The group is believed to have a large amount of influence on Government policy.
The ERG has also pressured Mark Carney, the governor of the Bank of England, over his gloomy forecasts for Britain leaving the EU.
Another member said: “Although hardcore Remainers – Nicky Morgan, Anna Soubry, Dominic Grieve and so on say they’ve learnt from Eurosceptics on how to rebel, it’s hard to say they are really battle hardened rebels.
“Steve Baker has rebelled using skills developed through the referendum, has significantly greater organisational experience and also knows what to devolve to other people.”
REMOANERS: These people hate BREXIT! Mon, January 16, 2017
Remainers are finding it hard to accept Brexit.
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The ERG seeks to influence Government, but ministers and whips are reportedly compelled to work with it.
A Government source said: “At the moment their influence is undeniable. Relationships with the whips are pretty clear.”
A leading member of the ERG also told the Times they get “anything they want”.
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