A row has broken out over plans to slow traffic on the Forth Road Bridge.
There have been fears drivers will be distracted by the progress of the Queensferry Crossing work.
MSPs were told by Transport Scotland project director David Climie that some were already slowing down to have a look.
What was being mooted was a 10mph drop in the speed limit on the bridge to 40mph, with average speed cameras installed on three miles of the A90 and M90 until the new bridge is completed at the end of next year.
The Forth Estuary Transport Authority (FETA), which is responsible for the existing road bridge, has questioned claims drivers are slowing.
Convener Lesley Hinds expressed her shock at the suggestion the matter of cutting the speed limit was a fait accompli.
Ms Hinds said FETA was responsible for setting the speed limit on the bridge.
“No formal request has been made by Transport Scotland, although some discussions have taken place regarding reducing the speed limit to allow new roadworks to be tied into the existing A90.
“We were, therefore, surprised to read comments made to MSPs suggesting that plans were already in place.”
She added: “We would also question Transport Scotland’s assertion that a reduction in speed limit is necessary due to distraction being caused by construction of the new bridge.
“As operators of the Forth Road Bridge we have seen no evidence that drivers are slowing down on the bridge and there has been no increase in accidents.”
She said FETA could not make a decision until it receives a formal request setting out the reasons for the proposed reduction.
While the new bridge will have a 70mph limit and intelligent transport system for variable speed limits, the project team has been in talks with FETA on planning for traffic management on the A90/M90 works north of the Forth Road Bridge for around 12 months.
A spokesman said the proposal to extend the 40mph limit across the bridge had been agreed by the project’s traffic management working group, including FETA, local authorities and Police Scotland.