Contractor Balfour Beatty, which is working on the £745 million project, has issued a statement about the delay.
Despite repeated calls for clarity over the timetable following Carillion’s liquidation in January, ministers had refused to revise the spring target for the 36-mile road.
Economy Secretary Keith Brown had said in January he hoped the bypass would open in April or May, but was unable to give an exact date.
The Scottish Government had flagged earlier this year it hoped the bypass would be finished by the spring, but has now said it was still trying to get an agreed date.
“The Scottish government continues to have discussions with Aberdeen Roads Limited (ARL) in order to achieve an agreed date for the earliest possible completion of this project, despite the recent insolvency of Carillion,” a government spokesman said.
“We expect these to conclude shortly and will provide a full update to parliament at that time.”
The bypass is one of the biggest infrastructure projects in Scotland.
Cost overruns on the project, which was first proposed to alleviate congestion in the Granite City in the 1950s, have been described as a key reason behind Carillion’s demise.
The new timetable emerged as Balfour Beatty announced its annual results, with the firm saying “completion is now expected in the summer of 2018”.