Scottish Tory leader Douglas Ross has been in talks with disgruntled SNP backbenchers to seek an end to the coalition with the Green party.

Mr Ross has refused to disclose who he had spoken to but his intervention days before the Rutherglen and Hamilton West by-election will raise tensions in what is a crucial test for SNP leader Humza Yousaf.

“I have spoken to members of the SNP who have raised concerns with me about the direction of their government and would look at ways that parliament can hold the SNP to account,” said Mr Ross, speaking at the Conservative party conference in Manchester.

“That clearly shows a frustration with some members of the current governing party in Scotland at the moment, that their own leadership is not listening to them.

He added: “I am saying I have been contacted and I have had discussions with backbench members of the SNP.

“They’ve come to me and we’ve had this discussion, and I think it just shows that what I’ve been articulating here at the Conservative Party conference about the areas of Scotland that have been forgotten by the SNP is clear not just to me but to members of the SNP.

“But they’ve got to make that choice. At the moment, largely they are still backing Humza Yousaf and his SNP-Green government.”

The partnership is under strain from a number of policy failures, such as the deposit return scheme, and last week Fergus Ewing, the former SNP cabinet minister, declared that the party “no longer puts Scotland first”.

He was suspended for backing a Conservative motion of no confidence in Lorna Slater, the Green minister.

Nine MSPs backed Ewing, who has said he will appeal against the punishment, and he was flanked by former Finance Secretary and leadership contender Kate Forbes, Annabelle Ewing, who is his sister and a deputy presiding officer at Holyrood, and Christine Grahame.

Ms Forbes and her allies have said on numerous occasions that the SNP should either renegotiate the Bute House agreement struck by Nicola Sturgeon, the former first minister, in 2021 to bring the Greens into government or ditch the pact altogether.