One of Britain’s biggest transport operators has promised to challenge legislation aimed at restoring local authority control on the buses.

A day after the government published its Bus Services Bill, Go-Ahead Group warned that ministers had not thought through the plans.

The bill’s premise is that mayors of big urban regions, such as Greater Manchester and Tyne and Wear, should have the same command-and-control powers over bus services as the mayor of London and Transport for London. Go-Ahead is the biggest operator in London’s regulated bus model, but under government plans it would be challenged in its historic home market around Newcastle.

It said that it “remains to be convinced that the application [of franchising powers] will deliver better services for our customers than the existing system of competition between operators and partnership working with local transport authorities”. It said it would follow the bill through parliament “and continue to help inform the debate”.

Go-Ahead, Stagecoach and FirstGroup, the country’s other big bus operators, believe that the government has not presented evidence showing that a TfL-style regulation of bus networks would provide better value for money if replicated outside the capital. They are trying to alter the legislation to ensure that there is an independent scrutiny body that will investigate the plans of any mayor.

Last year an independent investigation blocked the introduction of a “quality contracts scheme” in Tyne and Wear because the proposals could not be shown to be a better alternative. “Measures brought forward in the Bus Services Bill must ensure that the franchise decision-making process is transparent and that any franchise proposals will deliver on customer service, value for money and affordability criteria,” Go-Ahead said.

A Go-Ahead spokesman denied that the bus companies wanted to block the new system for financial reasons. Unregulated provincial services typically are better money-makers than the regulated TfL model. In Go-Ahead’s case, the differential in profit margins is 13 per cent, compared with 9 per cent.

“The margin we make [in unregulated markets] is reinvested to keep services sustainable and competitive, to upgrade to greener fleets and introduce wi-fi connectivity and to work hard to attract and retain customers in markets where we are competing with the cars and taxis,” the spokesman said.

Manchester is keen to take greater control of its market, which is dominated by Stagecoach and FirstGroup. It argued that despite greater ratepayer subsidy and capital support for buses, the number of passengers in the city region had stayed flat.

“The current bus system prevents bus services being joined up and co- ordinated with each other, as well as with other modes of transport such as rail and Metrolink [tram],” Transport for Greater Manchester said. “The number and variety of tickets in Greater Manchester is unduly complicated and passengers have to pay more for a ticket that works across more than one bus operator’s network.”

Ministers say that the bill will help to drive up bus use from 13 million journeys a day, will cut city congestion, drive economic growth and prompt investment in technology, such as smart one-card-goes-anywhere ticketing and smartphone apps to tell passengers when their next bus will arrive.

“We are determined to increase bus usage and these measures are designed to give councils access to a range of powers to help deliver regular, reliable services for all,” Andrew Jones, the roads minister, said.