Andrew Adonis said Saturday he will campaign next year to keep Britain inside the EU because following May's Brexit plans may lead to economic calamity.
“Very few of the people who voted for Brexit voted, I believe, to make themselves poorer,” he told BBC radio.
Adonis resigned Friday night as chairman of the National Infrastructure Commission to protest May's Brexit policy.
The Labour Party peer is urging other senior figures to speak out against Brexit, which he said would rip Britain out of its key trading alliances.
Britain voted in a 2016 referendum to leave the EU, but negotiations toward a new trading agreement with EU nations have been slowed by disputes.