British Prime Minister Boris Johnson on Friday promised to take the country out of the European Union by January 31 after his resounding election victory, Reuters reported.

“We will get Brexit done on time by the 31st of January, no ifs, no buts, no maybes,” Johnson told his supporters at a rally in London.

“Leaving the European Union as one United Kingdom, taking back control of our laws, borders, money, our trade, immigration system, delivering on the democratic mandate of the people,” he added. “We have won votes and the trust of people who have never voted Conservative before.”

The Conservatives secured a sweeping victory, winning more than 360 of the 650 seats in the House of Commons – the party’s largest majority since under Margaret Thatcher in the 1980s, The Guardian reported.

“You may only have lent us your vote, you may not think of yourself as a natural Tory [Conservative] you may hope to return to Labour next time round, and if that is the case, I am humbled that you have put your trust in me,” the prime minister said.

Prime Minister Narendra Modi congratulated Johnson. “Many congratulations to PM Boris Johnson for his return with a thumping majority,” he tweeted. “I wish him the best and look forward to working together for closer India-UK ties.”

Earlier in the day, British Labour Party leader Jeremy Corbyn said he would not lead the party into the next General Elections as it suffered a massive defeat. Corby, however, ruled out stepping down immediately.

“I will discuss with our party to ensure there is a process now of reflection on this result and on the policies that the party will take going forward,” he said from his Islington North constituency. “And I will lead the party during that period to ensure that discussion takes place and we move on into the future.”

However, a number of defeated Labour candidates asked Corbyn to resign immediately, blaming his leadership for alienating many working-class voters. Labour, which has been dogged by accusations of anti-Semitism under Corbyn’s leadership, said the party had become “the nasty party, the racist party”. “There is absolutely no justification for why he’s still there,” she added.

“I genuinely believe that the Corbyn leadership is the issue in this election and to say that it isn’t is delusional,” said Phil Wilson, who lost the election from former Prime Minister Tony Blair’s old seat of Sedgefield.

Johnson said it was a “powerful mandate to get Brexit done”. The Opposition party lost some of its traditional constituencies such as Darlington, Sedgefield and Workington, with these seats electing a Tory MP for the first time in decades.

The Scottish National Party also did well and even defeated Liberal Democrat leader Jo Swinson by 149 votes. Scotland’s First Minister Nicola Sturgeon said it had been an “exceptional night” for her party. Scotland had sent a “very clear message” that it did not want a Boris Johnson government and that the prime minister did not have a mandate to take Scotland out of the European Union, she added.