Lord Chris Patten has said he does not want Northern Ireland to go back to the days of "shooting and maiming" as he urged the Government to be "very careful" over how Brexit impacts on the border.
The Tory former Cabinet minister and ex-EU commissioner, who chaired a commission into policing in Northern Ireland as part of the peace process, said: "I feel emotionally very strongly about this. I think we did a really good job on the Good Friday Agreement. And I don't want to go back to the days when people were being shot and maimed.
"There is a simple answer to the Northern Ireland border question and to much else besides. Let's stay in the customs union."
The comments came as Lord Patten traded jibes with arch-Brexiteer Jacob Rees-Mogg, who likened opponents of withdrawal to a soldier who spent 29 years in the jungle because he did not believe the war was over.
Mr Rees-Mogg said: "With one year to go before the technical date of departure, this is the challenge to the decreasing number of Remainers who model themselves on Mr Hiroo Onoda, the Japanese soldier who finally surrendered in 1974 having previously refused to believe that the Second World War had ended."
Lord Patten hit back that Brexiteers lacked the experience to negotiate a trade deal, adding: "The closest they have come to a trade deal is the checkout at Waitrose."