The upgrading of the seven-mile section of the A8 dual carriageway between Glasgow and Edinburgh to complete the M8 has been put back from 2013 to 2017.
The Scottish Government yesterday announced it was now seeking firms to build the road – more than a year after ministers gave the plan their final approval.
That itself is believed to have been put back by the need to decide how it would be funded.
Ministers have still to say how much the project will cost, with a previous estimate of £210 million now years out of date. Construction is not now due to start for another two years, and will not be finished until after the 2014 Commonwealth Games in Glasgow.
The Baillieston to Newhouse scheme is expected to create more than 8,000 jobs over the next two decades and cut journey times by up to 20 minutes.
Company chiefs expressed dismay at the latest setback to replacing what they described as a “major business handicap”.
Opposition parties demanded that there be no further delays.
Infrastructure secretary Alex Neil said a “drastic cut” in Scotland’s grant from the UK Treasury meant the scheme could not have been progressed until now.
He explained this was because there was no money available to pay the expected £30m cost of land needed for the road, which will be built largely parallel with and to the south of the A8.
Ministers have decided to use their “non-profit distributing” (NPD) method for funding and building the motorway – a profit-capped version of the private finance initiative.
This mechanism is not thought to have been used before for transport projects in Scotland, and was ditched this year from the Borders Railway scheme after two of the three short-listed bidders pulled out.
However, experts have told The Scotsman that, despite being a novel method for funding roads, NPD should not be problematic and has been used before for schools.
The A8 upgrade will be accompanied by extra lanes on an adjacent stretch of the M8 in Glasgow, and on the nearby M73 and M74 motorways.
The project will also include improvements to the Raith interchange on the M74 at junction five, where the A725 provides links to the M8 and M77.
The combined cost was previously estimated to be £280-335m.
Glasgow Chamber of Commerce said the work must be speeded up.
Chief executive Stuart Patrick said: “We welcome this commitment to completion of the M8, but are also concerned that the anticipated date is now 2017 – four years on from the previous deadline.
“The fact that travel between Scotland’s two major cities is restricted to dual carriageway at points along the route continues to be a major business handicap.
“On the positive side, the gradual improvements in the connections between Scotland’s two major cities is allowing them to be seen as one labour market in international investment markets.
“We just need this process to be accelerated.”
Scottish Chambers of Commerce chief executive Liz Cameron said: “It is hugely welcome that this project is finally getting off the ground.
“The M8 upgrade will fill a real gap in Scotland’s transport infrastructure network.
“We are anxious to see construction get under way as soon as possible,” she continued. “In particular, there is concern that the link will not be in place before the 2014 Commonwealth Games.”
CBI Scotland’s policy executive, Lauren McNicol, said: “The completion of the M8 between Glasgow and Edinburgh has been a long-standing priority for our members.
“Improved connectivity is essential for the success of Scotland’s economy, and the building of this stretch of motorway is crucial to that success.
“We would therefore encourage no further delays to this project to ensure business can benefit from the reduced journey times and better connectivity that the Baillieston to Newhouse upgrade will ultimately bring.”
However, Labour accused ministers of not making the motorway a priority.
Uddingston and Bellshill MSP Michael McMahon, said: “This project has already been delayed for three years by the SNP government, which means that before a single inch of tarmac is laid, it will already be four years behind schedule. The constituency I represent has more people involved in construction than any other and is also a major hub for transport and logistics, so these delays have cost jobs.
“Businesses in this area have been crying out for improvements to help them trade and create jobs.”
He added: “It’s now vital that there are no further delays and this project is delivered as quickly as possible.
“The fact that we must now wait until at least 2017 for this improvement is evidence of the lack of urgency that the SNP government has applied to infrastructure investment.
“However, I welcome this move forward as it is vital to help kick-start a stagnant economy, where unemployment continues to rise faster here in Scotland than the rest of the UK.”
Liberal Democrat transport spokesman Jim Hume said: “The timetable for this upgrade has slipped again and again under the SNP.
“Heralding the start of the tendering process as a milestone will not wash with commuters, who expected the M8 upgrade to be completed by 2010.
“This work is vital for motorists who commute in and around Glasgow, Lanarkshire and to Edinburgh, and it is regrettable that the SNP are making people wait until 2017.”
The Scottish Government’s Transport Scotland agency said thet it had published a “prior information notice” to the construction industry, ahead of the official start of a competition to find a builder in the “spring”.
Transport minister Keith Brown said a review of the estimated cost of the scheme would be completed by then.
Mr Brown said: “This is a key delivery milestone of this significant project that will complete the last remaining gap in the central Scotland motorway network.
“On completion, it will further boost the nation’s economy by improving connections between the commercial centres of Glasgow and Edinburgh and beyond.
“Drivers can expect the M8 M73 M74 Motorway Improvements project to reduce congestion while enabling safer, quicker journeys.
“With benefits for drivers and businesses alike, this is a key enabler in helping promote sustainable economic growth by improving access to facilities and employment areas and reducing the time to transport goods and services.”
Transport Scotland announced that much of the new road would be separate from the current A8, so traffic disruption during construction “is likely to be minimal”.