Taxi laws need urgently updating to combat child sexual exploitation, councils have warned.
Some taxi legislation dates back to 1847 and needs strengthening to improve passenger safety following the proliferation of app-based firms and increased cross-border hiring, according to the Local Government Association (LGA), which represents more than 370 councils in England and Wales.
Councils are being frustrated at their inability to take enforcement action against the rising number of taxi drivers operating in their area but licensed elsewhere, the LGA said.
Some locally-based drivers must comply with more rigorous standards than other drivers operating on the same roads.
A working group to look at the issues was set up by the Government last autumn, and the LGA wants it to consider national minimum licensing standards for taxi and PHV drivers and a national database of all such drivers.
The LGA has recently commissioned the development of a national register of taxi and PHV licences which have been refused or revoked.
Deputy chairman of the LGA's safer and stronger communities board, Clive Woodbridge, said existing laws are "not fit for purpose".
Councils are "doing what they can" but the best way to strengthen safeguarding would be if the Government updates legislation, he claimed.
Mr Woodbridge went on: "We've seen a number of child sexual exploitation cases that have involved taxi and PHV holders abusing the trust that has been placed in them, so there are strong safeguarding reasons for strengthening current legislation.
"The onset of mobile phone booking apps for PHVs is causing concern about whether drivers are able to compete on a level playing field and has led to numerous and costly legal challenges which local licensing authorities are being forced to spend public money on."
Earlier this month taxi app firm Uber was accused by police of allowing a driver who sexually assaulted a passenger to strike again by not reporting the attack, along with other serious crimes.
In a strongly worded letter, inspector Neil Billany of the Metropolitan Police's taxi and private hire team suggested the company was putting concerns for its reputation over public safety.
He cited the case of a man who worked for Uber being allowed to stay on the books despite an allegation of sexual assault, leading to another "more serious" attack on a woman in his car.
A string of serious crimes it allegedly failed to report included more sexual assaults and an incident in which a driver produced what was thought to be pepper spray during a road-rage argument.
Uber said it was "surprised by this letter", adding: "In no way does it reflect the good working relationship we have with the police."