CONGESTION has been blamed for an "alarming decline" in the number of people travelling by bus in Glasgow, amid warnings that the problem "will destroy" the city's bus sector unless ballooning journey times are reversed.

A report today has revealed that bus speeds are falling faster in Scotland's largest city than anywhere else in the UK, and urged transport bosses to consider measures such as extra bus lanes or charging van drivers to make deliveries during peak hours to held ease the pressure on the city's roads.

Research by transport expert, Professor David Begg, found that bus speeds in Glasgow are falling by 15 per cent per decade compared to an average of 10 per cent for the rest of the UK.

This had contributed to a 22 per cent decline in passenger numbers across the Strathclyde region over the same period as commuters turned to rail or cars instead, he said, with bus patronage in the city forecast to drop by 10-14 per cent every 10 years if journey times continue to decline at the current rate.

Prof Begg said: "If you combine falling bus speeds with relatively cheap subsidised competition from an impressive urban rail network and cheap and abundant public car parking, it explains why Glasgow has experienced an alarming decline in bus patronage over the past decade.

"Traffic congestion is a disease which, left unchecked, will destroy the bus sector."

The findings, unveiled at Westminster, are the second part of Prof Begg's report 'The Impact of Congestion on Bus Passengers'. The first part, published in June, found that online shopping deliveries and the rise of Uber have contributed to a growing congestion crisis across the UK.

The report has been commissioned by sustainable transport campaigners, Greener Journeys.

First Glasgow, which runs a majority of the city's bus services, said congestion increased operating costs which, in turn, meant increased fares for passengers.

Its interim managing director, Alex Perry, said: "Sadly, significant falls in bus patronage are often portrayed as being primarily due to the actions of the bus operators.

"However, this report lays bare the significant impact congestion has on our city and on bus passengers."

Paul White, of the Confederation of Passenger Transport Scotland, the umbrella body for bus operators, said: “If we are to tackle the very real issue of congestion we need local authorities to make public transport a priority when allocating road space and considering infrastructure improvements.

"Bus operators cannot resolve this issue without assistance from the public sector."

Glasgow City Council was the first in Scotland to roll out camera-enforced bus lanes and has since introduced a bus gate barring cars from George Square and Nelson Mandela Place during the day.

However, it has also faced criticism for using the fines as a "cash cow".

Patrick Harvie, Scottish Green MSP for Glasgow, said the report showed that the free market model was "failing" and underlined the case for re-regulating Scotland's bus industry.

Bailie Elaine McDougall, the council’s executive member for Transport, Environment and Sustainability, said: “The council is committed to introducing measures that will make the use of sustainable transport options - including travel by bus - more attractive.

“Glasgow has been very proactive in promoting bus priority and continues to work positively with both the operators and SPT through the Statutory Quality Partnership.

“Our City Centre Transport Strategy recognises Renfield Street / Union Street corridor as being a key bus route through the city centre and we are about to start work to introduce traffic management measures which will reduce congestion and improve the flow of buses on this busy city centre street.”