The case is now on hold after the cabbies trade union, the LTDA, began separate proceedings against a number of Uber drivers in the magistrates court.
Leon Daniels, a senior executive at TfL, said the LTDA's action meant the High Court would refuse to consider the case until the criminal proceedings ended.
"I regret therefore that the essential and binding clarity about how the law should be applied in these circumstances will not be delivered for some considerable time."
Steve McNamara, of the LTDA said his organisation had issued summons against six Uber drivers alleging use of a private hire vehicle equipped with a meter. He said:
"We have no confidence in TfL's legal team at all, therefore we've issued private prosecutions in the magistrate's court.
"The meter isssue is a criminal matter. Let the criminal courts decide. TfL's legal advice is wrong and they are an impotent regulator."
A dispute which saw 5,000 cab drivers mount a blockade in central London looks to set to continue after a crucial court case was postponed. The cabbies are involved in a row with Transport for London over the growing use of mobile phone apps by mini cab firms.
The drivers claim the apps, used by companies like Uber, break the law because they calculate fares based on time and distance. TfL disagrees but has asked the High Court to give a "definitive and binding declaration".