The SNP's bid for more powers for the Scottish parliament is a "cop out" hiding the nationalists' failure to engage in a serious debate about public services, David McLetchie says this week.

In a speech to party officials and election candidates on Thursday, the Scottish Conservative leader will attack the nationalist approach to political debate north of the border.

And he will accuse the SNP of moving to the left of the political spectrum and being "terrified of losing even more ground" to Tommy Sheridan's Scottish Socialists.

"In the Scottish parliament, the SNP has routinely argued in response to the problems of the day that the parliament needs more powers," McLetchie will say.

"This is just a political cop out. People in Scotland want to know how we can improve our hospitals and our schools, reduce crime and create greater opportunity for everyone in our society.  In other words, what to do with the powers we have.

"We Conservatives accept this and want to engage in a serious debate about the here and now, but the SNP is more interested in talking about some never, never land flowing with milk and honey in which the grass is always greener."

And the Tory chief will also accuse the nationalists of being unable to offer an alternative to Labour and the Liberal Democrats, pointing out that they have opposed just three pieces of legislation put forward by the Edinburgh executive.

"The SNP is a self-proclaimed left of centre social democratic party just like Labour and the Lib Dems - so as matters stand, the SNP offers a change of passport, which people don't want, not a change of policy or approach for which I believe there is a real appetite," McLetchie will argue.

Alternative agenda

He will also highlight a Scottish political consensus around the need to "spend more, tax more and regulate more".

"Yet the response of the SNP to the failure of Labour and the Liberal Democrats has been to try to outflank them on the left.

"The SNP is so terrified of losing even more ground to Tommy Sheridan and his fellow Trots that they are engaged in a desperate battle to prove which is the most left wing party.

"Certainly the SNP is giving Tommy a run for his money.  The SNP has advocated an open doors immigration policy for an independent Scotland.

"It is unremittingly hostile to the whole idea of using private finance to build new hospitals, schools and prisons and scorns the whole concept of partnership with the independent sector to deliver public services.

"And its whole programme is based on the tired old solution of tax and spend."

McLetchie is set to say that the challenge for the Tories is to "prove that we understand the problems and then provide the solutions".

"If we do we will have proved that we are unquestionably Scotland's national party and be well on the way to achieving our goal of being, once again, a party of government in Scotland."

And with Alex Salmond tipped to take over the SNP leadership, the Scottish Conservative leader is also set to lambast his rival.

McLetchie will say it was Salmond's "political legacy which hangs like an albatross around the party's neck and will continue to do so".