The final cost of the parliament is said to be �373.9m

Building Magazine reports that it has been told by "a source close to the project" that certain parts of the complex are unlikely to be ready before July 2004.

Last month, officials said that MSPs would not be working on the new site at Holyrood until at least next April.

The source quoted by the magazine expected the next progress report issued by the parliament's Presiding Officer, George Reid, to contain more problems.

"The report is likely to show further slippages," the report said.

Two parts of the project - the office accommodation for MSPs and Queensberry House - should be completed by the end of the year.

The Holyrood scandal is a national embarrassment and the sooner it is over, the better Bill Aitken Tory MSP

But the magazine said delays were likely to hit other parts including the chamber and external works.

Despite a design freeze imposed in April, builders had been faced with 545 instructions from architects in May alone, it went on.

A Scottish Parliament spokesman said Mr Reid would continue to ensure "open and transparent" reporting on Holyrood.

Scottish National Party leader John Swinney said: "This project has gone from being a farce to a national disgrace."

The Conservatives' business manager, Bill Aitken, added: "The Holyrood scandal is a national embarrassment and the sooner it is over, the better."