The co-leader of the Scottish Greens has warned that failed SNP leadership candidate Kate Forbes is "building a particular faction" with her growing calls for her party to rip up the Holyrood power-sharing deal,

Green co-leader Lorna Slater, who is also the Scottish Government minister for circular economy and biodiversity, said Ms Forbes is “working on internal politics” within the SNP, while First Minister Humza Yousaf has established a “very progressive Cabinet”.

Following the last Holyrood election, the two pro-independence parties secured a parliamentary majority for the Scottish Government under the Bute House Agreement, making Ms Slater and fellow Green co-leader Patrick Harvie ministers for the first time.

There are currently seven MSPs in the Scottish Green group and 63 in the SNP’s.

The leaders said that Green MSP Ross Greer has a “pivotal” role in relations with the SNP, taking part in fortnightly meetings with the Deputy First Minister to stocktake on the agreement.

But Mr Greer raised eyebrows over the Scottish Government's Budget.

Mr Harvie said Mr Greer has put together a “coherent package” of requests which occasionally push their colleagues “beyond their comfort zones”.

But there is “good dialogue” between Government ministers and the respective spokespeople in the Green MSP group, he said.

Earlier in December, Ms Forbes called on the SNP to drop its powersharing agreement with the Greens and govern as a minority party.

SNP members overwhelmingly back the Bute House agreement and several backbenchers have been quick to point the finger at the Greens for their own party's internal troubles and policy problems.

SNP backbencher Fergus Ewing has been a vocal critic of the deal, blaming the Greens for unpopular policies and was disciplined by party bosses for failing to oppose a motion of no confidence in Ms Slater.

The Green leaders said they see no reason for the Bute House Agreement to come to an end before the next Holyrood election.

Ms Slater said: “I think it does show the power of the agreement.

“Kate Forbes is working on internal politics. She’s trying to build a particular faction.

“She didn’t win the leadership election, Humza did, and Humza has put into place a very progressive Cabinet.

“In many areas, they align with us, not all.”

During her ultimately failed leadership bid to replace Nicola Sturgeon as the next first minister, Ms Forbes launched her campaign with a stinging attack on the deposit return scheme, which Ms Slater has overseen and been heavily criticised for, claiming it was set to cause "economic carnage".

The majority of SNP parliamentarians and members back the idea of a stable pro-independence Government, she said.

Mr Harvie said: “The commitment from both ourselves and from the SNP is to deliver on everything that’s in that agreement.

“Now some of that is affected for example by UK budget cuts. We have to figure out how to manage that.

“So probably not every dot and comma of the Bute House Agreement will emerge as possible given the scale of those cuts, but we’re committed to delivering on it to the greatest degree possible and to embodying the values that are in it.”

He hailed the agreement as an alternative to the “toxicity” of polarised party politics.

Mr Harvie said the Scottish Government’s Budget had been “really, really tough” but his strategy for decarbonising heating in Scottish buildings had been preserved.

He acknowledged the supply of affordable housing would be “really challenging”, but said Westminster had “savaged” the Scottish Government’s capital budget.