Scottish Green Party co-convener Patrick Harvie has vowed to "push the Scottish Government beyond its comfort zone".

The Greens knocked the Liberal Democrats into fifth place and trebled their number of MSPs but Mr Harvie said there were "mixed feelings" in the party about the election result as some "fantastic candidates" had missed out.

The party highlighted plans to focus on fighting the controversial practice of fracking for shale gas, to push for an Act supporting farmers and local produce and to introduce "progressive" taxation.

HeraldScotland: Glasgow - July 30: Patrick Harvie MSP poses for a picture July 30, 2014 in Glasgow. (Photo by Mark Mainz). (47502631)

Speaking at an event in Edinburgh to launch the six newly elected MSPs, Mr Harvie said: "There are real opportunities in the next session for the Greens to push the government beyond its comfort zone but we're not at the point of being able to tell you exactly what those issues are going to be.

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"We've always - whether it's been facing a Labour-Lib Dem coalition, a minority government or a majority government - we've always been willing to be constructive where there is genuine common ground, we find this far more productive, and where necessary challenge where there are disagreements."

He added: "The case for progressive taxation is strong and they are going to require support to get the budget through."

Mr Harvie attacked Labour's performance and blamed them partly for the resurgence of the Conservative Party in Scotland.

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He said: "Clearly the Conservatives have been very successful and appealing on the issue of the constitution. They are the ones that have been raising persistently, and at every opportunity, IndyRef 2, far more than the pro-independence parties have been doing.

"But I think equally significant is the Labour Party's failure to present itself as a credible progressive force on the left of Scottish politics. It's lost the trust of a great many people and that's a big part of the reason why so much of their support has abandoned them."