Jack McConnell told MSPs: "I will do nothing - absolutely nothing - that will ever bring this parliament into disrepute."

He was asked by the Scottish National Party leader, John Swinney, for "full disclosure" of the alleged irregularities.

Mr Swinney said it would reassure the public there had been no breach of the ministerial code.

I regard the reputation of the post I am honoured to hold - and the reputation of this parliament - as something that is very, very important indeed

Jack McConnell

It has been alleged that a Labour activist may have used party funds without authorisation.

One newspaper report suggested a black hole in Mr McConnell's constituency accounts of up to �11,000.

The first minister told parliament: "I want to make absolutely clear in this chamber that there is no question - absolutely no question - that my constituency office accounts have even been questioned as part of this exercise.

"This is an issue about the local Labour Party's voluntary bank accounts.

John Swinney demanded "full disclosure"

"I have never seen those bank accounts, I should not need to see those bank accounts - but the Labour Party should, and that is what they are going to do" said Mr McConnell.

"And if they take action on that, they will have my full support."

Mr Swinney went on to ask Mr McConnell when he first became aware of the problem.

Why did the first minister not report it to the police?

John Swinney

He asked: "If he has known about it since February as the media suggest - and his party now say it may be the subject of a criminal investigation - why did the first minister not report it to the police?"

Mr McConnell said it was inappropriate for him to comment too much as that might prejudice any future investigation."

Earlier, the Scottish Conservative leader, David McLetchie, claimed the affair had similarities with the Fife constituency office scandal which forced the former first minister Henry McLeish to resign.

Mr McLetchie said: "If Mr McConnell wishes to avoid the fate of his predecessor, he must waste no time in clearing up this issue."

Tory leader: "Key questions"

He called on Mr McConnell to answer "key questions" about the accounts.

These included whether there was any public money involved, and whether rules on the disclosure of political donations were observed.

He said: "Mr McConnell cannot simply sweep this issue under the carpet. He must bring it into the open without delay."

A Labour spokesman said: "The Labour Party will have a full inquiry into the Motherwell and Wishaw constituency Labour party.

"This inquiry relates solely to the finances of a local Labour Party, which is a voluntary and private organisation.

"We will publish the results - but we will not allow the pace or scope of the inquiry to be dictated by the media or by opportunistic politicians flatlining in the polls."