The Greens are to stand candidates in just three of Scotland's 59 constituencies at the general election.
The party say they want to "target" campaigning in the areas where they have most chance of success but will not endorse any other candidates.
But pro-union parties have hit out at the move, accusing the pro-independence Greens of standing aside in favour of the SNP in an informal "Yes Alliance." It comes after senior SNP figures called for the Greens to consider such a move to avoid splitting the pro-independence vote in key seats.
The Greens are to contest Glasgow North where co-leader Patrick Harvie will stand after the party's success in large swathes of the constituency in last week's council election. The party will also contest Edinburgh North and Leith where they secured their best result in the 2015 election with Lorna Slater standing. Falkirk will also be contested by the Greens' Debra Pickering amid claims of "widespread concern" about fracking. None of these are target seats for the Conservatives.
Yvonne McLellan, Co-convener of the Scottish Greens' elections and campaigns committee, said: "Green teams around Scotland are focused on supporting our new councillors as they get to work helping communities and protecting public services. But they are also determined to reject the Tories' Hard Brexit disaster and fight for our future in Europe.
“Our volunteers and campaigners have put huge effort and financial resources into the Holyrood and local elections, and this effort has paid off with new Greens elected to represent their communities. Theresa May knows she can rely on self-interested wealthy donors and campaigners who’re allowed to break the spending rules without fear of prosecution. Greens don’t work that way, and we’re not in the pockets of the super-rich.
"That's why we are targeting our resources to build on our strong support in Glasgow North and in Edinburgh North & Leith, and also build support for the case against fracking in Falkirk. Greens across Scotland will support efforts in these constituencies, offering a bold alternative to the other parties.
"In the same way that the Greens in England focused efforts on Brighton to elect Caroline Lucas to Westminster, we believe by targeting we can work towards Scotland electing its first Green MP."