Firms are likely to face growing pressure to reduce corporate road travel and introduce employee car-share schemes after transport secretary Ruth Kelly increased funding for local congestion charge schemes and insisted there was now a "compelling argument" for car-share lanes.

Unveiling a raft of measures designed to tackle congestion, Kelly said that following a successful trial on the M42 near Birmingham the government had identified a further 800 kilometres of motorway that could benefit from using the hard shoulder as an extra lane.

She added that to ensure this extra road capacity does not "simply fill up", the government was considering measures that would reserve the extra lane for those either carrying a passenger or willing to pay a fee.

"There is a compelling argument for car share or charged lanes, which have been used for some time in the US," she said. "In order to get maximum benefit, access to car-share lanes is limited to vehicles carrying passengers, or single drivers willing to pay a toll."

According to a Department for Transport feasibility study, large sections of the M1, M6, M62, the M27 around Southampton, the M4/M5 near Bristol and sections of the M23, M20, M3 and M4 that feed into the M25 could all benefit from such road-widening measures.

The proposals are the latest in a line of initiatives to promote car sharing in the wake of government survey late last year that revealed that just one per cent of people are part of a formal lift-sharing scheme. The Department for Transport recently launched a best practice guide for corporate travel planning, including advice on how to form an employee car pool scheme. It is also working on the UK's first car-sharing lane near Leeds.

The latest package of measures also confirmed that the government has shelved controversial proposals for a nationwide road-pricing scheme that would use satellite technology to track people's movements and charge them based on which roads they used.

However, it committed extra funding to support local authority plans to introduce congestion charge schemes similar to the one that operates in London. Kelly said the government would extend the £200m-per-year Transport Innovation Fund supporting local road-pricing initiatives, which was scheduled to end in 2015, to 2019.

Greater Manchester and Cambridgeshire have submitted proposals for road-pricing schemes to the Department for Transport, and Kelly said she wanted to see more local authorities put forward plans.

John Day of the motorists' association the RAC broadly welcomed the new proposals, admitting that road pricing "has its place" in tackling congestion. However, he added that motorists would want to see funds raised from road-pricing measures reinvested in the road network.

Friends of the Earth argued that instead of increasing road capacity the government should be investing in improving alternatives to car travel. "Ruth Kelly's plans for extra motorway lanes are not the answer to Britain’s transport problems," warned transport campaigner Tony Bosworth. "The additional capacity will encourage more traffic, which may lead to more climate-changing pollution. And allowing drivers to pay to use one lane will only provide a choice for those who can afford it."