Theresa May has dismissed the idea of abandoning Brexit after the European court of justice ruled that the UK could stop the article 50 process without seeking EU approval.

The court in Luxembourg delighted remain campaigners by issuing an emergency ruling on Monday morning that, under EU law, the UK was able to unilaterally halt the article 50 process – fuelling renewed calls for a second referendum.

Speaking to MPs later as she fought to defend her decision to delay a Commons vote on her deal, the prime minister admitted the ECJ’s ruling meant she was able to revoke article 50 – a decision her government had bitterly opposed.

May was challenged by Liz Saville Roberts, a Plaid Cymru MP, who said the European court ruling meant it was in the prime minister’s gift to personally take Brexit off the table.

The prime minister indicated that was true but made clear she had no plans to do such a thing. It would be a short-term fix, she said, but would betray voters who won the 2016 referendum. “Revoking article 50 would mean going back on the vote of the referendum and remaining in the EU,” May said.

Scottish judges are to hold an emergency hearing in response to the ECJ ruling next week, chaired by Scotland’s most senior judge, Lord Carloway, the lord president, and two other judges, who now have to transpose it into domestic law.

Lawyers for the cross-party group of Scottish parliamentarians who took the case to Luxembourg are expected to argue it means the prime minister is lawfully able to cancel the article 50 process without needing new legislation.

Andy Wightman, the Scottish Green party MSP who led the legal challenge, said it was a momentous ruling which now meant the UK could stay in the EU and keep all its existing benefits, including its rebate, its opt-outs and the pound.

“MPs now know that stopping Brexit altogether is an option open to them before the end of the article 50 period,” he said.

Andy Wightman MSP (@andywightman) FULL CJEU #article50 ruling now published. Clear & unambiguous. Upholds our arguments. Having read submissions & heard evidence, there really was no other legal option. https://t.co/jDosCgCgj2 pic.twitter.com/bE7AcvoTQd

The pro-Brexit environment secretary, Michael Gove, played down the significance of the ECJ decision, which was announced just before he was interviewed on BBC Radio 4’s Today programme.

“We voted very clearly – 17.4 million people sent a clear message that they wanted to leave the European Union. And that also means leaving the jurisdiction of the European court of justice,” he said.

“So this case is all very well, but it doesn’t alter either the referendum vote or the clear intention of the government to make sure that we leave on 29 March.”

While the UK could abandon Brexit before 29 March, the date on which its withdrawal from the EU under article 50 takes effect, staging a second referendum would require the EU’s agreement to extend article 50 beyond its normal two-year time limit.

Rob Murray, a partner at the law firm Mishcon de Reya, which represented Gina Miller, the activist who won a supreme court ruling in 2016 that article 50 had to be authorised by parliament, said new legislation would be needed.

After reading the European court ruling, Murray said: “Critically, as clarified by the Miller decision, an act of parliament would be necessary to reverse the notification of intention to withdraw.”

Jolyon Maugham QC, the founder of the London-based Good Law Project, whose supporters helped fund the legal challenge, said he believed this was not necessary. All that was required, he said, was a Commons vote ordering the prime minister to stop Brexit.

“We’ll obviously need to discuss it internally. But I expect we’ll say that there’s no need for fresh legislation. Parliament can direct the PM to revoke and that’ll be that. It may even be that the government doesn’t disagree,” Maugham said.

He cited reports from Sky News that government ministers also privately believed no new legislation is required. However, the case is expected to be vigorously contested by the UK government, which could appeal against it to the UK supreme court in an effort to delay a final ruling.

The ECJ judgment, which came only two weeks after it held an emergency hearing on the issue, had itself been expedited to coincide with the crucial vote on May’s Brexit deal in the Commons tomorrow.

That vote has now been postponed as May fights to save the deal and her government after more than 100 Tory MPs, including numerous loyalist, pro-remain backbenchers, threatened to vote the deal down.

Maugham and other members of his group believe the ECJ ruling raises doubts about the supreme court’s ruling in Miller in 2016 because it was partly based on the assumption that article 50 could not be unilaterally revoked.

Miller’s legal team and the UK government agreed to that position because it was legally simpler to do so, Maugham said, and increased the constitutional role of parliament. The European court has now said that was wrong.