Mr Livingstone and transport commissioner Bob Kiley are urging the European parliament to amend a proposed regulation which will require almost all public transport across the European Union to be put out to tender every five years.
The mayor yesterday told a delegation of French mayors, elected officials and transport operators that in its present form the regulation would have 'serious negative consequences for public transport in many UK and European cities, including London'.
'If the regulation were to go ahead in its present form it would make it compulsory for even large, complex metro systems like the London Underground to put out to tender every five years. The result would cause chaos,' said Mr Livingstone.
'It is vital for the efficiency and safety of UK and European public transport services that the regulation is amended,' he told the delegation of 20 French officials.
Mr Livingstone's concerns are already shared by RATP, the operators of public transport services in Paris, and the Mayor is keen to hear the views of other French officials.
The mayor is working with cities and transport operators across the EU to persuade MEPs who are due to vote on the proposal in July to make important changes.
Mr Livingstone said the regulation had other serious problems:
* It could lead to the creation of private sector monopolies dominating public transport
* It could cost London hundreds of millions of pounds in compensation payments and disrupted service
* It would prevent authorities from intervening to maintain services where private sector operators were unable to do so
* The five-year limit on contracts would discourage operators investing in high quality services
The new regulation, which was drafted by the European Commission, is called the Regulation on Public Service Requirements in Passenger Transport.