Nicola Sturgeon has revealed her SNP Government is in talks with the Scottish Greens over a possible formal co-operation agreement, saying that by working together the two parties “can help build a better future for Scotland”.

The First Minister announced details of the talks as she set out her priorities after the SNP won the Holyrood election earlier this month.

She stressed discussions between the two parties – which are being supported by the civil service – will continue over the coming weeks, and said it is “not inconceivable” that they could see Green MSPs joining the SNP in the Scottish Government.

Ms Sturgeon said the parties are “agreeing to come out of our comfort zones to find new ways of working for the common good”.

She added: “As we embark on this process, we are setting no limits on our ambition.

“So in that vein let me be clear that while this is not a guaranteed or a pre-agreed outcome, it is not inconceivable that a co-operation agreement could lead in future to a Green minister or ministers being part of this Government.”

The First Minister’s comments came as she set out her “unashamedly ambitious” plans for the coming days and months, also making clear her intention to hold a second Scottish independence referendum and insisting it would be “undemocratic” for the UK Government to block one.

She promised the first 100 days of her new Government will see a consultation take place on setting up a National Care Service – hailing this as “the most important public sector innovation” since the NHS was established.

The 100-day plan will also see the “first phase” of work to recruit 3,500 more teachers and classroom assistants for Scotland’s schools, in a bid to help youngsters whose education has been disrupted by coronavirus.

Ms Sturgeon told MSPs: “Our programme is rooted in today’s reality. But it also shows the way to a brighter tomorrow.”

As part of that, she said “people in Scotland should have the right to make that choice”, once the health crisis is over.

The SNP failed to win an outright majority at Holyrood but she said the inclusion of the Greens means there is a “substantial majority” of MSPs in favour of an “independence referendum within the current term”.

Ms Sturgeon declared: “There is no justification for the UK Government seeking to block that mandate.

“To do so would suggest that the Tories no longer consider the UK to be a voluntary union of nations. And it would be profoundly undemocratic.”

Scottish Green Party co-leader Lorna Slater said she hopes the talks with the SNP on a formal co-operation agreement will allow them to “deliver real change”.

She said: “The Scottish Greens have always worked constructively with other parties, delivering meaningful change like free bus travel for young people, and earlier this month the public returned the largest ever Green group to Parliament to take that work further and faster.”

Fellow Green co-leader Patrick Harvie added: “Politics does not have to be about point-scoring and short-termism. Green parties across Europe and in countries like New Zealand have in recent years rolled up their sleeves and worked with other parties to deliver a better future.

“But they have also shown that there is more than one way for government and opposition parties to work together, without losing the ability to challenge one another.

“We believe the people of Scotland want to see grown-up politics like this, and will approach the forthcoming talks in this spirit.”

But Scottish Conservative leader Douglas Ross hit out at the First Minister, saying it had taken “just 15 seconds for Nicola Sturgeon to talk up the prospect of another referendum” in her key statement.

Mr Ross told MSPs: “Nicola Sturgeon speaks of bringing people together then pushes the most divisive proposal imaginable.

“This isn’t a speech to unite Scotland, it is not a statement of the people’s priorities, it is a regurgitation of the SNP’s top priority.”

Scottish Labour leader Anas Sarwar referenced previous support the Greens have given the SNP in budget votes, saying it is “good to see the Greens formalising and accepting their longstanding coalition of cuts”.

He added: “Let’s be clear this isn’t day one of an SNP Government. It is day 5,136.

“If the First Minister is serious about focusing on recovery, she must commit in the first 100 days to make this recovery meaningful.”

Scottish Liberal Democrat leader Willie Rennie said the “emerging Green pact is a sign that independence is the overriding priority”.

He added: “The First Minister promised this would be a Parliament focused on recovery and she would defer a referendum until the effects of the pandemic were over.

“I’m disappointed to see the First Minister announce plans which would push the recovery aside.”