The future of transgender rights in Scotland remains in limbo, as SNP politicians warn that a leadership contest must not become dominated by ongoing rows on gender recognition reform.

Meanwhile, Scottish Greens sources suggest that any rowback on reform could lead to the collapse of the party’s power-sharing agreement with the SNP.

A key challenge for whoever replaces Nicola Sturgeon is whether to continue with her plan to challenge the UK government’s decision to block Holyrood’s gender bill through the courts.

Scottish government sources confirmed on Thursday that ministers were still taking legal advice on the prospect of challenging the section 35 order that was announced by the UK government in January, which prevents the bill from going for royal assent. They said a decision was unlikely to be reached until much closer to the 16 April deadline.

On Thursday evening, the SNP’s national executive committee confirmed that the results of its leadership contest would be announced on 27 March, giving the new leader just over three weeks to decide.

A number of SNP politicians, both supportive of and opposed to the bill, raised concerns that the leadership election could become mired in the increasingly toxic debate that has dogged the party for several years, leaving voters unclear whether the party shares their priorities.

One MP said: “People on the doorstep are not talking to me about GRR but about the cost of living crisis. The leadership contest shouldn’t become all about the bill. The contest must concentrate on what to do to unify the party and lead us to independence.”

While Sturgeon was an unapologetic defender of the legislation, which would simplify how an individual may legally change their gender, Scottish equalities campaigners have raised concerns that a new leader less committed to reform – as at least one potential contender is known to be – might offer concessions to the UK government rather than formally challenge section 35.

Another SNP MSP who was closely involved in the bill’s progress through Holyrood said that while they expected at least one candidate to emerge who was opposed to the reforms, they would be surprised if the new leader did not continue with the legal challenge.

“This is about much more than gender reform, it’s about whether the Scottish parliament can pass its own legislation. I’d be surprised if a nationalist leader didn’t challenge that, and I’m much more concerned about winning that challenge,” they said.

A Scottish Green party source said the party’s joint leaders, Patrick Harvie and Lorna Slater, would almost certainly resign from their ministerial posts if the new SNP leader either delayed or rewrote the gender recognition bill.

That would lead to the collapse of the formal cooperation deal brokered by Sturgeon and Harvie in 2021, which led to the SNP sharing power for the first time. “It’s a red line for the party,” he said. “There’s no compromise on this.”

Sturgeon’s successor would almost certainly see that threat as another significant argument in favour of fighting to keep the bill on track. “I think they would walk if a new SNP leader didn’t do everything in their power to get that bill on to the statute book,” the source said.

He also suggested that if the government watered down or dropped the bill, SNP MSPs would revolt in far greater numbers than the nine SNP backbenchers who voted against it.

Senior SNP sources suggest the successful leadership candidate must offer a robust defence of the bill itself but also open up dialogue, while shifting focus to other pressing domestic concerns such as heating and healthcare.

The SNP MP Joanna Cherry, a vocal critic of the changes, tweeted immediately after Sturgeon’s resignation announcement that a leadership contest must “restore the SNP’s tradition of internal party democracy, open respectful debate and intellectual rigour”.