The promise is part of the county's bid for £500 million from the government's transport innovation fund (TIF). The council's cabinet is meeting this week to look at the recommendations.
The trigger point, which would have to be agreed by the government, should only come in when congestion reaches unacceptable levels.
The report follows advice from an independent transport commission, which said a congestion charge should not be implemented until at least 2017 and only after transport improvements (Planning, 31 July, p6).
A full bid could be submitted at the end of next year. But first Cambridgeshire will seek government assurance of funding for the construction of Chesterton station, which would start in 2012.
The council's cabinet member for growth, infrastructure and strategic planning Roy Pegram stressed: "Without introduction of the congestion charge, the city will become gridlocked." A decision will be made by the council on 13 October.