Voters are being urged to unseat prominent Brexit-supporting MPs such as Iain Duncan Smith, Theresa Villiers and Kate Hoey by the successor organisation to Britain’s pro-EU remain campaign.

Open Britain has drawn up an “attack list” of 20 seats, held mostly by Conservative MPs, where constituents voted to stay in the EU but their representatives are Brexit supporters.

Open Britain hopes to mobilise the half a million supporters it has on its database to oust them.

The pressure group believes the disconnect between the politicians and their voters over the issue of Europe provides the chance to eat into or even overturn large majorities. The ultimate aim is to limit the number of proponents of hard Brexit in parliament.

The same aim was voiced in a call for tactical voting by campaigner Gina Miller and an intervention by Tony Blair.



Lord Mandelson, an Open Britain board member, claimed it was counterproductive for prime minister Theresa May to enter Brexit negotiations with a rigid set of red lines and said he believed millions of jobs were at stake.

“Election candidates of all parties should be demanding that a hard Brexit is rejected and making clear that they will reserve judgment on the outcome until they see whether we get exactly the same trade benefits, as [Brexit secretary] David Davis has promised,” he said.

Open Britain has teamed up with two other grassroots pro-EU organisations, European Movement and Britain for Europe, providing access to 600,000 supporters for what it has dubbed its “20/20 key seat strategy”.

As well as the 20 seats marked out for attack, the group has drawn up a list of 20 Labour, Liberal Democrat and Conservative MPs who have been powerful advocates of the closest possible relationship with the EU27. They plan to provide activists to help defend these MPs – many of whom have constituencies that backed Brexit.

Stephen Dorrell, the former Tory MP who chairs European Movement, said: “This election is about something much bigger than party politics – it is about our future relationship with the rest of Europe.

“Pro-Europeans need to stand up and be counted between now and 8 June. The supporters of our organisations want to be know where they can make a difference in this campaign and we are providing the tools for them to be able to.”

The intervention comes as Blair writes in the Guardian, claiming it is not enough for Labour to run a conventional campaign against cuts and the NHS when Brexit is so dominant.

He said he was not advocating tactical voting but did support cross-party campaigns against “Brexit at any costs”.

“Ignoring the Brexit issue or trying to downplay it as one issue out

of many just won’t work … we have to expose the fact that the mandate the Tories are asking for is not an open negotiation in the interests of the country but for a Brexit at any cost driven by the ideology of the right of the Tory party,” he wrote.

“Yet if this is seen as a narrow Labour point, it will be much less persuasive. Hence the absolute necessity, in the Labour interest, of rallying people to a more reasonable and open position on Brexit across the party divide.”

Many of the attack seats are in London or the south-east, including Chingford and Woodford Green, which is held by the former cabinet minister Duncan Smith, with a majority of 8,386 over Labour. One estimate says it voted 51% to remain although the referendum vote was not broken down by individual constituencies so others have claimed a narrow leave victory in the seat.

Duncan Smith said the groups were welcome to target his constituency but argued that there was no point re-fighting the referendum. He said the general election was about stable leadership against chaos “and they seem to be on the side of chaos”.

Open Britain and the other groups said they had produced a list of constituencies to campaign in because of pressure from thousands of activists who were keen to get involved and wanted to know where to focus their energies.



The list of 20 “defence seats” include many MPs in leave areas, including Labour’s Mary Creagh, Angela Smith and Pat McFadden as well as the Lib Dems’ Norman Lamb and Tom Brake.

Conservative Neil Carmichael, who has spoken out in favour of soft Brexit from the prime minister’s backbenches, will be supported against Labour in his constituency of Stroud, Gloucestershire, where 46% of voters backed leave.

Villiers will be targeted in Chipping Barnet, north London, where it is estimated there was a 59% remain vote. She holds the seat with a majority of 7,656 from Labour.



She said: “I have a strong track record as a local champion for Chipping Barnet, campaigning on the issues that matter to my constituents. The referendum divided every constituency. My goal is a to make a success of the Brexit decision the country made in the referendum and deliver a new deep and special partnership with our European neighbours, with which both leave and remain voters can be comfortable.”

The groups will also pour resources into Wycombe in Buckinghamshire, which is held by the prominent leave supporter Steve Baker, a Tory MP.

The pro-EU groups are even planning to target Tory MPs who supported remain in June’s referendum but have failed to speak out against a hard Brexit if their general election opponents arefiercely pro-EU.

For example, James Berry, the MP for Kingston and Surbiton, who is being challenged by the former Lib Dem cabinet minister Ed Davey, is on the list.

The only Labour MP in the attack list is Kate Hoey in Vauxhall, where Lib Dem candidate George Turner will be supported in his attempt to overturn a 12,000 majority in a constituency that voted 78% to remain in the EU.

The Liberal Democrat leaflet opposing Kate Hoey.

The Lib Dems have produced an image of Hoey’s face merged with Nigel Farage, after his former party, Ukip, backed her in the seat.

James McGrory, the co-executive director of Open Britain, said the best way to fight hard Brexit was to cut its proponents in parliament.



“Open Britain has over half a million supporters and lots of them have asked what’s the best thing they can do in the election,” he said. “This is what we’re telling them – one of the best ways they can help is by campaigning against those who favour Brexit at any cost.”

Polls continue to show the Conservatives leading Labour, with the latest ICM/Guardian survey giving them a 21-point lead.

Seats to attack

Iain Duncan Smith

Conservative

Chingford and Woodford Green

Majority: 8,386

Campaigned for leave

Estimated vote in constituency: 51% remain

Kate Hoey

Labour

Vauxhall

Majority: 12,708

Campaigned for leave

Estimated vote in constituency: 78% remain

Theresa Villiers

Conservative

Chipping Barnet

Majority: 7,656

Campaigned for leave

Estimated vote in constituency: 59% remain

Steve Baker

Conservative

Wycombe

Majority: 14,856

Campaigned for leave

Estimated vote in constituency: 52% remain

James Berry

Conservative

Kingston and Surbiton

Majority: 2,834

Campaigned to remain, but accused of not speaking out against hard Brexit

Estimated vote in constituency: 58% remain

Seats to defend

Mary Creagh

Labour

Wakefield

Majority: 2,613

Campaigned to remain

Estimated vote in constituency: 63% leave

Pat McFadden

Labour

Wolverhampton South East

Majority: 10,767

Campaigned to remain

Estimated vote in constituency: 68% leave

Norman Lamb

Liberal Democrat

North Norfolk

Majority: 4,043

Campaigned to remain

Estimated vote in constituency: 58% leave

Neil Carmichael

Conservative

Stroud

Majority: 4,866

Campaigned to remain

Estimated vote in constituency: 54% remain

Caroline Lucas

Green

Brighton Pavilion

Majority: 7,967

Campaigned to remain

Estimated vote in constituency: 74% remain