MSPs will sit in the new parliament building next year

Tory chief whip Bill Aitken had called on MSPs to back their demands that Thursday afternoon's business be changed to allow the statements to be made.

Mr Aitken said there was "considerable public concern" following last week's revelation that the costs had gone up again from £338m to £375m.

He said the latest price hike meant the project was "not only seen by many as a national scandal but also as an international embarrassment".

The First Minister can hide no more. He must make a statement to the Parliament in order that we can at last begin to move on Bill Aitken MSP

The Glasgow MSP added: "There is very real anger now with regard to this entire farce and it is incumbent upon the First Minister in particular to do his best to resolve matters speedily.

"The First Minister can hide no more. He must make a statement to the Parliament in order that we can at last begin to move on."

The Tories were backed by the SNP, whose business manager Bruce Crawford said it was "vital" that Mr McConnell make a statement on his plans to hold an inquiry into the Holyrood debacle.

'Rumour and misinformation'

He added: "In place of clarity we get rumour and misinformation. It's time for the confusion to be ended. It's time for the First Minister to make his statement to Parliament."

But they were defeated by 70 votes to 44 after Labour and the Liberal Democrats joined forces to block it. One MSP abstained.

Parliament minister Patricia Ferguson defended the executive's position and pointed out that Labour backbencher Janis Hughes was due to ask the First Minister about the proposed inquiry at Question Time on Thursday.

"I'm sure Mr McConnell will take that opportunity to outline in as much detail as possible what is proposed," he said.

The Tories have demanded that any probe should take the form of an independent public inquiry headed by a senior legal figure and with the power to call Westminster ministers involved in devising the project between 1997 and 1999.

A spokeswoman for Mr McConnell said on Wednesday that he would make an announcement on the investigation "as soon as possible".

He briefed fellow ministers on the latest developments at Wednesday's weekly cabinet meeting and has also been discussing the matter with opposition party leaders, she said.