Willie Gallagher is the chief executive of Tie
Edinburgh City Council's deputy leader has called for the boss of the city's tram project to resign.
SNP group leader, Steve Cardownie wants Tie chief executive Willie Gallagher to quit following traffic gridlock on the first day of road works at the Mound.
On Wednesday, Mr Gallagher was forced to make a public apology for temporary traffic measures "not fully working".
Lib Dem leader Jenny Dawe, Edinburgh City Council leader, said she had convened an urgent meeting
Edinburgh City Council is lead by a coalition between the SNP and the Liberal Democrats.
Mr Cardownie, whose party has campaigned against the tram scheme, said it was "outrageous" that the works could go so "disastrously wrong".
He told the BBC Scotland news website: "It was just terrible on Wednesday, I had to make two U-turns to get home as it was pandemonium.
"Calton Road was chock-a-block and I just inched down Leith Walk in my car.
"The buck has to stop somewhere, so I would say that would be the chief executive. It's not a personal attack on Willie, but he is responsible so he has to resign.
"How could it have gone so badly and how do we know it won't happen again? With power comes responsibility."
He added that he would phone Mr Gallagher to ask him for answers over what happened on Wednesday.
Ms Dawe said: "In light of the intolerable disruption caused to city residents and workers by the start of tramworks at the Mound, I have convened an urgent meeting with Tie, who are responsible for managing the delivery of Edinburgh's tram project, and senior council officers in charge of transport across the city.
"Our response to this will not be a knee-jerk reaction calling for somebody's head.
"If the investigation into the incident shows that traffic modelling failed or individuals were culpable then that will be addressed.
"We want to ensure that the tram project has the best people working on it for the duration of the contract."
The city centre was gridlocked during the morning rush hour, with buses being held up for an hour and some passengers getting off to walk to work.
Princes Street is closed to traffic for six months while underground pipes are moved.
Services which pass through the busy junction are either being diverted via George Street or Market Street.
Full pedestrian access is being maintained during the project.
The utility diversions will prepare the area for the laying of tram infrastructure on Princes Street, which is scheduled to start in January 2009.
Mr Gallagher said: "The impact of these changes reminds all of us that the city centre is already very near to full capacity with the many different forms of traffic.
"These experiences are providing us with useful lessons and experiences when we come to deliver the tram installation works from January next year."
Graham Birse, Edinburgh Chamber of commerce deputy chief executive, said: "It's inappropriate and unrealistic to ask for the resignation of the chief executive of Tie at this time.
"You don't solve problems by getting rid of the person in charge of a complex project at this point.
"It would only lead to more delays and lengthen the project. The council should be looking to its own responsibility for supporting the management of the project, having appointed Willie Gallagher and set up Transport Initiatives Edinburgh."