Boris Johnson is set to announce a £5 billion cash injection to overhaul bus and cycle links in English regions outside London.
The Prime Minister will say the five-year funding package will provide more frequent services and simpler, more affordable fares.
It will also allow for new priority bus routes and the purchase of at least 4,000 zero-emission buses in England and Wales.
Details will be set out in a Commons statement on Tuesday in which Mr Johnson is expected to confirm the HS2 high speed rail link is to go ahead, despite concerns about the costs and the impact on the environment.
Local transport connections have a truly transformative role to play in levelling up infrastructure across the countryBoris Johnson
The move will be seen as a sop to placate Tory MPs critical of HS2 who have argued the money would be better spent on improving local transport links in the North and the Midlands.
As well improving bus services, Mr Johnson will promise 250 miles of new cycle routes across England, with dozens of “mini-Holland” schemes to make town centres safer for cyclists.
Before the announcement, Mr Johnson said: “Local transport connections have a truly transformative role to play in levelling up infrastructure across the country.
“Our daily journeys for work or leisure are about so much more than just getting from A to B – they are the key to accessing skilled jobs and opportunities, boosting businesses and unlocking economic growth for towns, cities and regions across this country.
This unambitious announcement is nowhere near enough to make the difference that transport users, our economy or our environment needAndy McDonald
“That’s why improving connectivity by overhauling bus services and making cycling easier than ever is such an important step forward, to make sure every community has the foundations it needs to thrive.”
Shadow transport secretary Andy McDonald said the measures would not reverse the damage done by years of Conservative cuts.
“After years of under-investment and cuts, this unambitious announcement is nowhere near enough to make the difference that transport users, our economy or our environment need,” he said.
“The Conservatives are refusing to reverse their colossal £645 million-a-year cuts to bus budgets, which have caused thousands of routes to be axed and fares to soar.”
Darren Shirley, chief executive of Campaign for Better Transport, said: “This is a significant step change from the Government and welcome news for communities up and down the country who have borne the brunt of poor or non-existent local public transport in recent years.
“Appropriately allocated, this funding should help to improve air quality and drive down carbon emissions by supporting the transition to zero emission vehicles; reduce fares and speed up journey times; and restore lost services and routes that have left many communities disconnected.”
British Cycling policy adviser Chris Boardman said: “We know that investment in cycling and walking has the potential to transform Britain’s towns and cities into healthier, cleaner and more vibrant places to live and work, but getting there will require far more than just 250 miles of segregated lanes. We hope that this is just the start of the new Government’s ambitions, and await further details of their long-term cycling programme and budget with interest.”