LONDON (AP) – British Prime Minister Boris Johnson pledged Saturday to repay the trust of voters in the working-class heartland of northern England who rejected the Labour Party and helped give him an 80-seat majority at this week’s election.

Speaking to cheering supporters at a cricket club in Sedgefield – the constituency once held by Labour former prime minister Tony Blair – Johnson acknowledged the seismic shift that helped sweep him to victory in Thursday’s election.

“I know that people may have been breaking the voting habits of generations to vote for us,” he told supporters. “And I want the people of the northeast to know that we in the Conservative Party and I will repay your trust.”

In a victory speech outside 10 Downing Street on Friday, Johnson called for an end to the acrimony that has festered throughout the country since the divisive 2016 Brexit referendum, and urged Britain to “let the healing begin.”

Johnson’s campaign mantra to “get Brexit done” and widespread unease with the leadership style and socialist policies of opposition leader Jeremy Corbyn combined to give the ruling Conservatives 365 seats in the House of Commons, its best performance since party icon Margaret Thatcher’s last victory in 1987. Labour slumped to 203 seats, its worst showing since 1935.

While Johnson was on a victory lap Saturday, Corbyn – who has pledged to stand down next year – was under fire from within his own party, where there was little sign of healing starting any time soon.

WATCH | Bishop Auckland MP @HelenGoodmanMP is trying to trick her 61% Leave-voting seat into thinking she hasn't been trying to stop Brexit. Her record says otherwise! Here she is laughing like a child in the Commons while Brexit legend @CatharineHoey speaks out for the 17.4m… pic.twitter.com/Tr2cWWLSLv — Leave.EU (@LeaveEUOfficial) November 18, 2019

Former lawmaker Helen Goodman, one of many Labour legislators to lose their seat in northern England, told BBC radio that “the biggest factor was obviously the unpopularity of Jeremy Corbyn as the leader.”

Another former Labour lawmaker criticized the election campaign more broadly as muddled. Anna Turley told the BBC that the party put forward an overwhelming number of policies and voters “just didn’t believe we were the party that could deliver on any of it.”

John McDonnell, Labour’s finance spokesman, said Saturday he would stand down from the position when Corbyn is replaced.

“I’ve done my bit. We need to move on at that stage with that new leader,” he told reporters.

Armed with his hefty new majority, Johnson is set to start the process next week of pushing Brexit legislation through Parliament to ensure Britain leaves the EU by the Jan. 31 deadline. Once he’s passed that hurdle – breaking three years of parliamentary deadlock – he has to seal a trade deal with the bloc by the end of 2020.

“We’ve just been going over the timetable we can definitely get it in before Christmas, and we’re out on Jan. 31,” Johnson said.

While Johnson’s large majority means he has relatively clear air ahead on Brexit, he faces turbulence over renewed calls for a referendum on Scottish independence following the strong election showing of the Scottish National Party.

The front page of Saturday’s edition of The Scotsman newspaper featured photos of Johnson and Scottish National Party leader Nicola Sturgeon and the headline: “Two landslides One collision course.”

Johnson owes his success, in part, to traditionally Labour-voting working-class constituencies in northern England that backed the Conservatives because of the party’s promise to deliver Brexit. During the 2016 referendum, many of those communities voted to leave the EU because of concerns about immigration and neglect by the central government in London.

We said we wanted to stop a second referendum. And tonight, there will be lots of seats won by the Conservatives because The Brexit Party has taken Labour votes that would never go Tory. pic.twitter.com/SdYbbkaTMG — The Brexit Party (@brexitparty_uk) December 12, 2019

In Sedgefield, he paid tribute to his new lawmakers who turned those concerns into a big election victory.

“Thank you for your wonderful achievement in transforming our party, transforming the political map of this country,” he said.