Two Green MSPs will become Scottish Government ministers under a new confidence and supply agreement between the party and the SNP.

The agreement, which has been negotiated over a number of months, will cement the pro-independence majority in Holyrood and commits to seeking a new referendum on the issue in the first half of the parliamentary session – if the Covid-19 pandemic is over.

A document published on the Scottish Government website on Friday said two Green MSPs will be nominated to become ministers – the first time the party has taken such a role in the UK.

Under the terms of the deal, Green MSPs would support the Scottish Government on confidence votes, as well as in annual budgets if there is “appropriate funding for the shared policy programme”.

However, a number of areas are excluded from the agreement, including much of aviation policy, the future of green ports, and direct financial support to businesses involved in the aerospace, defence and security sectors, field sports and the economic principles related to concepts of sustainable growth and inclusive growth.

Both sides hailed the deal, which is yet to be approved by Scottish Green Party members, as a “historic moment”.

Speaking from her official residence at Bute House in Edinburgh, First Minister Nicola Sturgeon said: “The publication of this agreement today undoubtedly marks a historic moment.

“It recognises that business as usual is not good enough in the times we are living through.

“It grasps that out of great challenge, a better world and a better Scotland is capable of being born, but it understands that achieving it will take boldness, courage and a will to do things differently.”

She said the parties will work together to build a “greener, fairer, independent Scotland”, but stressed it is “not a coalition” and while they do not agree on everything they are focusing on areas of agreement.

Ms Sturgeon said the agreement makes it “impossible” for the UK Government to withhold the powers for a second Scottish independence referendum as it intends.

Speaking at the same press conference, Scottish Greens co-leader Patrick Harvie said: “This is indeed a historic moment.

“This deal would see Greens entering government for the first ever time in Scotland, or anywhere in the UK.

“And it couldn’t come at a more important time.

“The last 18 months have been an incredibly difficult time for us all and as we seek to rebuild our lives and our economy we really must seek to do things differently.“

The PA news agency understands a meeting of the Scottish Cabinet approved the powersharing deal on Friday morning.

The two parties have been locked in negotiations since May, after the SNP fell one seat short of an overall majority at the Holyrood election.

The agreement stops short of a formal coalition between the two but they pledge to work together on key issues, including on a Scottish independence referendum after the coronavirus pandemic.

The Scottish Conservatives and Labour have raised concerns about a deal.

Scottish Tory net-zero spokesman Liam Kerr said the Green manifesto from May’s election was a “doctrine to start a war on working Scotland”, after it proposed a move away from North Sea oil and gas, and the end of new road-building projects.

Scottish Labour leader Anas Sarwar has challenged the Greens to stand against further cuts to council budgets.

He said: “If the Greens are to be anything more than simply the SNP’s lackeys, they need to rediscover their principles and fight for a greener Scotland rather than roll over to the SNP every time the going gets tough.”