Brian Cox said Nicola Sturgeon has “huge shoes to follow” as he warned members of the SNP they must make sure her resignation as Scottish First Minister did not become a setback for the independence cause.

The 76-year-old actor, who plays Logan Roy in HBO hit Succession, has often spoken of his support for Scotland leaving the UK, and told Andrew Neil’s Channel 4 programme of his “admiration” for the outgoing SNP leader.

“We have to be careful that it isn’t a setback (for Scottish independence)”, Cox said on Sunday.

He said Ms Sturgeon had “huge shoes to follow”, and added on the leadership election: “I think we’ve got to get it right. We’ve really got to get the right person.”

He had backed Constitution Secretary Angus Robertson to take over as SNP leader and first minister, but Mr Robertson did not throw his hat into the ring.

Voting in the contest to replace Ms Sturgeon opens on Monday, with SNP members having the choice of Finance Secretary Kate Forbes, Health Secretary Humza Yousaf and former community safety minister Ash Regan to become the country’s sixth first minister.

“The other people I think are interesting, but I worry about the fact the party needs that same vision that’s been so present with Nicola,” Cox said.

“The problem with the party is it’s a wide, broad church. And now that Nicola’s going you’re seeing the extent of what that church is and that’s the difficulty – finding who can take over and carry on what she has done so remarkably well.”