LONDON - Sturgeon, the leader of the Scottish National Party (SNP), said she had held discussions with the Greens, who have promised to support a second independence referendum, at her official residence on Tuesday.
The SNP had been hopeful of winning an outright majority in elections this month which would have strengthened their call for a secession vote but they fell one seat short of the 65 required in the 129-seat devolved Scottish parliament, partly because of an electoral system that helps smaller parties.
With the support of the Greens, who have seven seats, the SNP would have a clear majority to pass legislation to push ahead with plans for another referendum once the COVID-19 pandemic is over.
"I can confirm that the Scottish Government and the Scottish Green Party will enter structured talks, supported by the civil service, with a view to reaching, if we can, a formal co-operation agreement," she said.
"Exactly what the content, extent and scope of any agreement will be is what the talks will focus on, but what we hope to achieve is potentially groundbreaking."
A referendum bill would set up a bitter clash between the Scottish government in Edinburgh and Prime Minister Boris Johnson's United Kingdom-wide administration in London, with Scotland's 314-year union with England and Wales at stake.
The British government argues Johnson must give approval for any referendum and he has repeatedly made clear he would refuse. He has said it would be irresponsible to hold one now, pointing out that Scots had backed staying in the United Kingdom in a "once in a generation" poll in 2014 by 55%-45%.
(Reporting by Andrew MacAskill; editing by Michael Holden)