SNP delegates have backed Humza Yousaf’s new strategy demanding talks begin on Scottish independence if the party wins a majority of seats at the next General Election.

His proposal, promoted alongside Westminster leader Stephen Flynn, secured overwhelming support at the party’s annual conference in Aberdeen.

With boundary changes reducing the number of constituencies in Scotland from 59 to 57 it means the SNP needs to win 29 for it to claim a mandate to begin separation talks with Westminster.

The first minister had initially proposed a strategy based on the SNP winning the “most” seats, which could be much lower than 29 if many other parties won seats.

Mr Yousaf told delegates that the party’s manifesto would say “on page one, line one: Vote SNP for Scotland to become an independent country.”

Under his predecessor Nicola Sturgeon’s proposals the SNP would need to secure a majority of votes cast in Scotland and and amendment was tabled by MP Pete Wishart to back this approach. He said it would give “credibility” and “legitimacy” to the Scottish government’s case for a referendum on the international stage.

He argued that a strategy based on a majority of Scottish seats would be “laughed out” by the UN. However, his amendment was rejected by delegates.

Neither the Conservatives or Labour are likely to support talks even if the SNP wins a majority of seats.

Chris McEleny of the breakaway Alba Party, said: “The SNP position is now that if they lose over 20 seats at the General Election but still win a majority then that will act as a mandate to ask for a referendum for the fifth time. We all know what the answer will be.

“By this new strategy Scots would then wait until 2026 to find out if it’ll be “mibbees aye or mibbees naw” that the Scottish Parliament election will then be a defacto referendum.

“This isn’t a strategy for independence, it’s a strategy to try keep Humza Yousaf in a job after the General Election.”