Transport bosses say they face a tough deadline to progress with plans to build a metro extension in Birmingham city centre.
Last month the city council finally agreed its desire to run the line underground was not currently feasible and reaffirmed its backing for the street level option from Snow Hill to Five Ways.
Meanwhile, the Passenger Transport Authority and executive Centro had been waiting for the decision in order to submit a final business case to government for both this and another extension to Brierley Hill in December.
Centro believes this timetable is essential to have both lines running by 2011.
A steering committee has been set up so the city council and Centro-PTA can thrash out remaining differences over the exact route of the city centre line.
Last week Birmingham transport cabinet member Coun Len Gregory refused to rule out making alterations to the route, although this might delay the project further.
At a meeting of the PTA yesterday, Centro managing director Rob Donald admitted time was tight but reassured PTA councillors that Birmingham was committed to the plan.
"Two months to get an agreement is shorter than we would have liked but there is a true belief in Birmingham at cabinet and officer level in metro as part of their future transport plans."
He was responding to comments from PTA councillors imploring all concerned to "get on with it".
Coun Renee Spector (Lab Erdington) said: "How ready are we to start this timetable of work?
"December is not that long from now, it is a very short period of time and in my experience if you do not begin on time you do not finish on time."
Coun Roger Horton (Lab Soho and Victoria), the PTA spokesman on metro matters, added: "I hope Birmingham will cooperate with this because everything else has come together. As far as I am concerned 2011 is too far away, I'd have the thing built tomorrow if I could but the first deadline is December and we simply must meet it."
The PTA agreed to welcome Birmingham's renewed commitment to the on-street metro line and noted the fact the city council would like to progress the Birmingham Airport/NEC route as the next priority line.