FORMER Attorney General Dominic Grieve says he has received a death threat after an investigation was launched about alleged links between foreign governments and the MPs behind the Benn Act which could force Boris Johnson to delay Brexit.

Mr Grieve, the Beaconsfield MP, was one of the Conservatives who were expelled by Mr Johnson after voting against the government in support of the act which the Prime Minister said "scuppered" his negotiations with the EU.

Mr Grieve is understood to have handed the email threat to the police. 

It comes after Number 10 took what was described as "unprecedented action" over the alleged collusion.   Officials claimed to have intelligence that MPs had received help drafting the bill from members of the French Government and the European Union.

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“I have not colluded,” Mr Grieve. “We did it off our own bat. And what’s more, talking to the EU is not a criminal offence, so it’s a double lie from No 10. It’s like living [in] a totalitarian state. The death threats have been coming in. I’ve had one on the train up to Manchester this afternoon.”

The MP said that the claims coming from Downing Street were "not true" and that all they serve to do is "diminish trust levels" that the public have in politicians.

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Speaking to Bloomberg News, Mr Grieve said:“This is quite a regular correspondent. He e-mails to tell me I’m wrong quite often but this afternoon he told me I should be killed. It will go to the police tomorrow.”

Mr Grieve said this "whipping up the heat may be electorally advantageous further down the road, but it's a very dangerous thing to do in a democracy, because once you start this, you start to raise the temperature on all sides... and above all, if you start telling lies and saying things you have no rational basis to believe are true, you are doing a very grave disservice, and it's a rather unconservative thing to do".

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A No 10 source reportedly said: "The Government is working on extensive investigations into Dominic Grieve, Oliver Letwin and Hilary Benn [who tabled the Bill] and their involvement with foreign powers and the funding of their activities. Governments have proper rules for drafting legislation, but nobody knows what organisations are pulling these strings.

"We will demand the disclosure of all details of their personal communications with other states. The drafting of primary legislation in collusion with foreign powers must be fully investigated."