Scottish National Party leader Alex Salmond has had talks with Green MSPs about "parliamentary co-operation" after the next Holyrood election.
The meeting took place in Edinburgh before Christmas at SNP headquarters.
Mr Salmond and SNP Holyrood business convener Bruce Crawford met Green MSPS Mark Ballard and Patrick Harvie for a discussion which lasted for two hours.
Mr Harvie said that the "informal" talks had identified "common ground" between the two parties.
The SNP leader described the meeting as "friendly and constructive" but played down speculation about a future coalition.
He called them "exploratory talks on the parliamentary situation that is likely to develop after next year's elections".
"The SNP intends to become the largest party in the parliament," Mr Salmond said.
"The Greens, I'm sure, will be a parliamentary force in that parliament and you would expect the parties to be preparing for the situation where we would be able to replace the current discredited Labour executive with a different one."
Holyrood MSPs - Party breakdown
129 MSPs at Holyrood
Scottish Labour 50 seats
Scottish National Party 25 seats
Scottish Lib Dems 17 seats
Scottish Conservatives 17 seats
Scottish Greens 7 seats
Scottish Socialists 6 seats
Independent 5 seats
Scottish Senior Citizens 1 seat
Presiding Officer 1 seat
He described the meeting as a "good one" and said there were likely to be more discussions in the future.
The SNP leader said that a coalition between the two parties was just one of the possible outcomes.
"There are areas of parliamentary co-operation which stop short of coalition," he said.
"Obviously the Greens and ourselves have differences but equally we have very substantial points in common.
"On current political issues like rendition flights or nuclear power, we are both strongly against these, and above all, of course, both parties believe in Scottish independence."
Mr Harvie said: "Alex Salmond's approach is recognising that the Greens are a serious force in Scottish politics, that we're going to be on the political map for some time to come and that where we have common ground, it's good to talk.
Of the 129 MSPs, 25 are SNP and seven Greens.
The current Labour/Lib Dem executive has 67 seats.