As a poll has warned that backing Brexit would be more damaging to Labour's electoral fortunes than the Iraq war, a report by ITV News and the Guardian said it will cost the party 45 seats at a snap election, compared with 11 for opposing Britain's departure.
"There can be no disguising the sense of disappointment and disillusionment with Labour if it fails to oppose Brexit and there is every indication that it will be far more damaging to the party’s electoral fortunes than the Iraq war," the report said.
“Labour would especially lose the support of people below the age of 35, which could make this issue comparable to the impact the tuition fees and involvement in the coalition had on Lib Dem support.”
Moreover, the poll added that the party would also risk losing five of its seven MPs in Remain-supporting Scotland if it supports Brexit.
"Even if we accept that most Labour voters would not desert the party for a new centrist party, anger at Brexit means that some will," the report added.
But, according to the study, four-fifths of Labour's supporters believe Theresa May’s deal will hurt the British economy. 91.4% do not trust her to deliver a Brexit that will be good for people like them.
"If there is an election in 2019, Labour will get a lower share of the vote in every seat in the country if it has a pro-Brexit policy than if it has an anti-Brexit position,” the report warned.