Jim Wallace was deputy first minister at Holyrood

Jim Wallace made his claim during a lecture at Glasgow University on Monday evening.

The former Scottish Liberal Democrat leader also suggested a Lords place for the first minister to enable closer links between MSPs and Scottish MPs.

He said such a role would improve areas like energy, where there was a shared responsibility.

Mr Wallace told the gathering: "Perhaps even more radically, further reform of the House of Lords could provide an opportunity for some representation of the Scottish Parliament and Welsh and Northern Ireland assemblies."

Maybe the lesson is to be bold, to consult and take people along with you, and build a wide coalition of support Jim Wallace former deputy first minister

Looking back over the start of devolution in Scotland, Mr Wallace admitted that he and others could be accused of having oversold it.

He said: "I don't believe that any of us ever did claim it was a shortcut to Nirvana, but there was an expectation that somehow all previous ills would disappear."

Reviewing its achievements, he cited the legislative ban on smoking in public places as a particular success.

"Maybe the lesson is to be bold, to consult and take people along with you, and build a wide coalition of support," said Mr Wallace.

He also went on to suggest a fresh "review" of local government.

Done deals

This should not get bogged down in boundary disputes but be an honest examination of areas where policy was determined nationally but managed locally.

It should also identify those issues where there could be real local policy making, said Mr Wallace.

His warning of the practical difficulties of minority government came as the Greens prepare to decide this weekend what their approach should be to any coalition talks.

The Scottish Parliament election takes place in 2007

The party at present favours an arrangement where, if they hold the balance of power, they would seek to negotiate a deal.

This would involve the Greens supporting another party - in return for concessions to Green policies - in the election of a first minister and pledging not to vote against that party in any no-confidence vote.

But Mr Wallace warned minority government would be hard to sustain in the long term.

"Whatever its superficial attractions, the reality is that ministers would have to work away on their boxes, undertaking all the mundane but essential duties with no knowledge - let alone guarantee - that their precious piece of legislation will pass through tomorrow's committee or Wednesday's debate in the chamber," said Mr Wallace.

Deals done to secure or defeat a particular amendment would lack the transparency of a partnership agreement.

"The media would love it, ministers would quickly tire of it, and the public would regard the instability with disdain," he said.