LONDON (AP) — Scotland's leader told British Prime Minister Boris Johnson Sunday that a second Scottish independence referendum is “a matter of when, not if," after her party won its fourth straight parliamentary election.

Johnson has invited the leaders of the U.K.’s devolved nations for crisis talks on the union after the regional election results rolled in, saying the U.K. was “best served when we work together” and that the devolved governments in Scotland, Wales and Northern Ireland should cooperate on plans to recover from the coronavirus pandemic.

But Nicola Sturgeon, Scotland's first minister and leader of the Scottish National Party, told Johnson in a call that while her immediate focus was on steering Scotland to recovery, a new referendum on Scotland's breakup from the rest of the U.K. is inevitable.

Sturgeon reiterated “her intention to ensure that the people of Scotland can choose our own future when the crisis is over, and made clear that the question of a referendum is now a matter of when — not if,” her office said.

Earlier, she said she wouldn't rule out legislation paving the way for a vote at the start of next year.

Final results of Thursday’s local elections showed that the SNP won 64 of the 129 seats in the Edinburgh-based Scottish Parliament. Although it fell one seat short of securing an overall majority, the parliament still had a pro-independence majority with the help of eight members of the Scottish Greens.

Sturgeon said the election results proved that a second independence vote for Scotland was “the will of the country” and that any London politician who stood in the way would be “picking a fight with the democratic wishes of the Scottish people.”

Johnson has the ultimate authority whether or not to permit another referendum on Scotland gaining independence. He wrote in Saturday’s Daily Telegraph that another referendum on Scotland would be “irresponsible and reckless” as Britain emerges from the pandemic. He has consistently argued that the issue was settled in a 2014 referendum where 55% of Scottish voters favored remaining part of the U.K.

But proponents of another vote say the situation has changed fundamentally because of the U.K's Brexit divorce from the European Union. They charge that Scotland was taken out of the EU against its will. In the 2016 Brexit referendum, 52% of U.K. voters backed leaving the EU, but 62% of Scots voted to remain.

When asked about the prospect of Johnson agreeing to a second Scottish referendum, Cabinet Office minister Michael Gove said Sunday “it’s not an issue for the moment” and stressed that the national priority is on recovering from the coronavirus pandemic.

Gove argued that the SNP's failure to secure a majority in the Scottish Parliament was in marked contrast to the party's heights of power in 2011, when it won a 69-seat majority.

“It is not the case now — as we see — that the people of Scotland are agitating for a referendum," he told the BBC.

The Scotland results have been the main focus of Thursday's local elections across Britain. In Wales, the opposition Labour Party did better than expected, extending its 22 years at the helm of the Welsh government despite falling one seat short of a majority.

Labour's support also held up in some big cities. In London, Mayor Sadiq Khan handily won a second term. Other winning Labour mayoral candidates included Steve Rotherham in the Liverpool City Region, Andy Burnham in Greater Manchester and Dan Norris in the West of England region, which includes Bristol.