The prime minister has announced a referendum on Britain's membership of the EU.

David Cameron's meeting with Cabinet ministers at Number 10 on Saturday fired the starting gun on the referendum race, as Eurosceptic ministers are now allowed to campaign for a Leave vote.

He announced the vote after returning from lengthy talks in Brussels where he secured a deal to reform Britain's membership of the EU, which takes effect if the country votes to remain, with key parts requiring legislation from the European parliament.

It includes measures to cut child benefit payments for children living overseas, to halt in-work benefit payments for migrants in the event of "exceptional" levels of migration, and for Britain to keep the pound while being in Europe without fear of trade discrimination.

Mike Penning, the MP covering Kings Langley, confirmed he would vote to leave.

He said: "When I cast my vote in the referendum I will not be voting as MP, but for me personally, expressing what I believe to be best for my family and for our country.

"It is now clear that joining the Euro would have been an economic disaster for this country given the recent troubles in the Eurozone.

"Now the same people who said our economy could not survive if we didn’t join the Euro are saying a vote to leave the EU will be a disaster. They were wrong then and they are wrong now.

"We should take back our sovereignty so that laws affecting the way we live are made by the MPs we elect to represent us at Westminster. It is as simple as that.

"I will not be joining any of the ‘Leave’ groups but will take the opportunity, if asked, to express my long-held views."

Hertsmere MP Oliver Dowden said he would not announce his decision until he has met with his association.

London mayor Boris Johnson ended weeks of speculation last night by announcing his plan to campaign for Britain to leave Europe.

A referendum which will seal the fate of the country's EU membership will be held on June 23.

Wondering how MP's in Hertfordshire are going to vote? Click here.

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