Theresa May meeting troops in October 2018 (Picture: MOD).
A former head of the UK's intelligence services and former Chief of the Defence Staff are urging MPs to reject Theresa May's Brexit withdrawal deal on grounds of national security.
In a letter obtained by Sky News, Sir Richard Dearlove and former defence chief Lord Guthrie have written to the chairs of Conservative Party associations across the country warning the Prime Minister's deal "will threaten the national security" of the UK.
The letter goes on to say Mrs May's withdrawal agreement "cuts across" the UK's membership in NATO and relationship with the United States and that the deal would give "foreign hands" control of Britain's national security.
It then asks MPs to vote against the agreement.
Tory former Brexit secretary David Davis said on Twitter: "Few people can match the expertise and patriotism of Richard Dearlove and Charles Guthrie. People should pay serious attention to their considered letter on why the PM's Withdrawal Agreement needs to be voted down next week."
A Downing Street spokeswoman responded to the letter, saying: "The claim is completely wrong.
"Nothing in the Withdrawal Agreement or our Political Declaration cuts across NATO, our defence or intelligence relationship with the USA or with the Five Eyes alliance."