SCOTTISH Labour leader Richard Leonard has left the door open to sweeping changes to his party’s candidate selection process that could produce a “cull” of his MSPs.

The embattled leader, who led Labour to fifth place at the European election, twice declined to say whether he is in favour of his party’s governing body being able to select List candidates for Holyrood.

In a wide-ranging interview, the Central Scotland MSP also appeared to criticise Jeremy Corbyn's office for its handling of Scotland during the European campaign. He said:

- Labour made a mistake in putting Jeremy Corbyn’s face, rather than his own, on European election literature

- There are “some battles” that need to be “re-fought” with the UK party on autonomy

- There is a case for responsibility for party disciplinary cases being transferred to the Scottish party

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Leonard, a left-winger, recorded the worst ever result for Scottish Labour when his party won 9% of the vote at the European election.

His critics believe his lukewarm attitude towards a second Brexit referendum cost them thousands of votes.

However, following the result, Leonard performed a u-turn and said his party unequivocally supports a confirmatory vote on any Brexit deal.

Speaking to the Herald on Sunday, Leonard shifted his focus to the 2021 Holyrood election and said he would present a “radical” social and economic agenda to voters.

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However, his allies believe he is being undermined by MSP colleagues, a majority of whom did not vote for him during the Scottish Labour leadership contest in 2017.

They believe Leonard needs to ensure that left-wing candidates replace some existing MSPs ahead of the 2021 poll.

One idea is for Labour’s governing Scottish Executive Committee (SEC), which has a left wing majority, to be able to rank the first two candidates on each of the eight regional lists. Party members currently possess this right.

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This would give party bosses the power to select 16 candidates who would stand a fair chance of being elected. Serving MSPs would be at risk of not making the cut.

It is understood MSPs have already raised questions about this idea at Labour group meetings in Holyrood.

Asked whether he would be in favour of the SEC being able to rank some of the candidates, Leonard said: “That will be up to the SEC.”

Asked the question again, he said: “It’s something the Scottish Executive, in the end, to make a decision on that.”

He added: “In each different Scottish Parliament election, from 1999 onwards, there has been a different system employed for selecting people for the List. So we shall see.”

On whether he wanted new blood in the Labour group after 2021, Leonard said he wanted “additional blood”, adding:

“I want to see the bedrock of the existing group be considerably increased.”

A party source criticised the plan: "This would lead to a cull by the hard Left. After his humiliation at the ballot box, Richard should show some humility, distance himself from the hard Left, work to bring the party back together, and rule this out.

"But the greater threat is that Labour ends up with so few MSPs this issue becomes irrelevant."

In the interview, Leonard conceded that the UK party's decision to use Corbyn's face, not his own, on a Scottish Labour European election campaign leaflet had been a mistake.

He said: “I’ve had conversations with Mark Drakeford, the First Minister of Wales, and we both agree that that was a mistake, because his picture wasn’t on the leaflet in Wales either."

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Put to him that it had not been decision, he said: “In the heat of the election campaign, which was called at very short notice, it would have been, in my view, better to have Mark Drakeford’s picture on the leaflet in Wales and better to have my picture on the leaflet in Scotland.”

He added: “The leaflet that you describe originally had a text which didn’t recognise that we’ve got different challenges facing public services in Scotland. And so we had to re-write the text."

Asked whether the picture decision was made by Corbyn’s communications director Seamus Milne, Leonard said: “I wasn’t involved in the negotiations about that."