Holyrood’s sole Alba Party MSP has set out the demands she will make to First Minister Humza Yousaf in exchange for her support in a crucial no confidence vote.

The First Minister faces a vote on his leadership next week, with former SNP MSP Ash Regan in a critical position after the Scottish Greens confirmed they will vote against Mr Yousaf following his decision to end the Bute House Agreement.

Ms Regan has been a fierce critic of some Scottish Government policies, including gender reform, previously quitting her ministerial post over legislative proposals.

She later defected to Alba, led by former SNP first minister Alex Salmond, and is the party’s Holyrood leader and only MSP.

In a letter to Alba members, Ms Regan said she is “carefully considering” her position ahead of the vote.

She has also written to Mr Yousaf to offer him an “early opportunity” to discuss three clear priorities – Scottish independence, women’s rights and the future of the Grangemouth oil refinery.

A spokesman for the First Minister said Mr Yousaf will be writing to Ms Regan and all other Holyrood leaders, adding he “looked forward to meeting with her to discuss a range of issues – including Grangemouth”.

Ms Regan suggested in her letter to Alba members that investment in the refinery, which could shut as early as next year and shift to an import and export terminal, could be the price for her support.

The Alba Party has already launched a campaign to protect jobs at the Grangemouth refinery.

She said: “A sign of good faith would be a significant Government investment, reinforcing the campaign to save the Grangemouth refinery from closure.

“I am requesting the undertaking to produce such an initiative in the early course. I am hopefully that the First Minister will commit to such an initiative in the near future as a sign of our shared dedication to Scotland’s welfare.”

Ms Regan also said recent legislation had “fallen short” of protecting the rights of women and children, urging Mr Yousaf not to put “ideology” before “evidence-based science”, as she called on the Scottish Government to consider how to implement the recommendations of the Cass Report into gender healthcare in England.

She will also urge Mr Yousaf to back proposals for an independence convention on Scottish sovereignty.