Alex Salmond announced last night that the SNP was now working on preparations to go it alone at Holyrood as a minority administration, with limited support from the Greens.

He emerged from coalition talks with the two Green MSPs, Robin Harper and Patrick Harvie, full of praise for the constructive way the meeting had gone.

Negotiations will resume today but any deal is likely to fall short of a full coalition with the Greens, who prefer a looser form of support known as "confidence and supply".

This "loose" co-operation means voting in favour of SNP ministers and their budget in exchange for policy input, but without accepting ministerial positions.

But Mr Salmond said there would be no coalition talks with the LibDems while they insisted on the precondition that the SNP drops its aspirations for a referendum on independence.

"Forming a minority government is now our working assumption, although our offer to the Liberal Democrats of negotiations without preconditions remains open," said Mr Salmond.

"I am very disappointed at not getting into talks with the Liberal Democrats, but they may feel - and it is perfectly honourable and understandable - that a period in opposition may be their preference."

A deal with the Greens still leaves Mr Salmond 16 votes short of a majority, but if Tories and LibDems abstain he would not need that majority to become First Minister.

Mr Salmond said of the prospect of ruling without a majority in the parliament: "Being in a minority presents its own challenges. We would not get everything our own way and would need to look at what we can and cannot get done."

He said of the challenge ahead: "It means we will need to show great clarity of purpose. It will also greatly enhance interest in the parliament, with every vote crucial, and will keep the government on its toes.

"It will present challenges but it could be done with goodwill, good all-round government and a government that showed itself to be nimble of brain and light of foot, and not prepared to be knocked off course in the event of the odd setback."

He added: "All this is new to Scotland but not elsewhere in Europe. Denmark, for example, has never had a majority government since the Second World War and yet every government has lasted a full term."

Asked about instability or the prospect that opponents at Holyrood could engineer the collapse of a minority government, forcing fresh elections, he said: "I think that is hugely unlikely. I think the job of parliamentarians is to get on with carrying out the wishes of the electorate."

Deputy LibDem leader Tavish Scott said his party's position was clear and "does exactly what it says on the tin".

He denied that going to the back benches would dilute their influence, adding: "Are we going to be the hand-maidens to independence? No. Minority government might be very exciting. To say any of us will be more neutered is not the case."

He also insisted Sir Menzies Campbell had put no pressure on them not to deal with the SNP. "There has been no heavy-handed pressure whatsoever."

The two Green MSPs and the party's other co-convener, former MSP Shiona Baird, began talks with civil servants at St Andrew's House in Edinburgh yesterday morning, before being joined by former SNP leader John Swinney, who has been handed a key negotiating role by his party.

They were then joined by deputy SNP leader Nicola Sturgeon before Alex Salmond joined the talks at 2pm. These were scheduled to run until 4pm, but it was closer to 4.30pm before all six emerged.

Afterwards Robin Harper said they had discussed "issues both of common ground and of difference with the SNP," adding: "There is a duty on all parties to seek to secure a stable and progressive government for Scotland.

"Our top policy priority is to deliver the necessary action on climate change and transport. More discussion is required on these issues before any agreement can be reached and we are looking forward to engaging in those constructively."

Mr Salmond said they might have to differ with the Greens on some individual transport projects, such as a Forth crossing. "Reflecting on areas of difference like that we can see areas where confidence and supply might be more appropriate than coalition," he said.

SNP clashes...