The Scottish Executive has announced that the completion date for the Aberdeen bypass has been put back another year.
The bypass is aimed at improving safety and the economy
Transport Minister Stewart Stevenson said the original timescales were "unrealistic".
A completion date of 2012 is now being targeted for the Aberdeen Western Peripheral Route (AWPR).
Local Lib Dem MSP Mike Rumbles said the delay would add millions of pounds to the project's costs.
The transport minister announced a review of a number of Scotland's transport projects, including the bypass, after the Scottish National Party's election victory.
Mr Rumbles blamed the setback on "dithering" by Mr Stevenson over the scheme.
The West Aberdeenshire and Kincardine MSP said: "It was made clear to the minister when he announced his review into the AWPR that this would inevitably lead to a delay in the project and an increase in costs, and this has proved to be the case."
He called for the executive to publish in full the results of its review to see "what has led to this delay".
"The Executive must tell us what action it will be taking to try to make up this lost ground," Mr Rumbles added.
Aberdeen business leaders welcomed confirmation that the road will be built.
Geoff Runcie, chief executive of Aberdeen and Grampian Chamber of Commerce, said: "These big projects are almost always inevitably delayed."
Campaigners against the bypass have called for a public inquiry into the project.