Edinburgh is being strangled by a “huge circle of congestion”, the head of its main bus operator has warned council leaders.
Lothian Buses managing director Richard Hall said buses must be given greater priority to help ease the gridlock.
He said the capital’s evening rush hour was now starting as early as 1pm and lasting up to six hours.
Mr Hall said the morning rush hour also began as early as 6:30am and continued until 9:30am.
He called for bus lane hours to be extended to cover the longer homeward-bound traffic peak after they were reduced two years ago.
He fears motorists are deterred from switching from their cars by buses being caught in traffic jams and simply drive into the city centre instead.
Mr Hall said: “There is a huge circle of congestion around Edinburgh stretching as far as the outskirts, which strangulates the whole city.
“There has been investment in the trunk road network but that is not joined up with local policy.
“A huge flow of cars effectively reaches a wall.
“The challenge is how we disperse that traffic and make it move across the city.
“Congestion is absolutely killing our industry. Bus operators are trying to combat that but we can only do so much.”
Mr Hall said he had lobbied “very hard” for longer bus lane hours and for the lanes to be lengthened, without success.
He said: “They need to be operating in daylight hours.
“The evening peak is now 1-2pm to 7pm, yet bus lanes operate only from 4 to 6:30pm and there is congestion from 2:30-4:30pm.
“Bus lanes should start at the bottom of the A1 [from the east] so you hit the priority before the queue starts.”
However, the city council said it had no plans for more bus priority.
Since 2015, most all-day bus lanes have been reduced to peak hours only.
Transport and environment convener Lesley Macinnes said: “We live in a growing, busy, successful city.
“More people are moving around, and in and out of the city, than ever before.
“To reduce congestion we need to get more people to choose public transport as the better option – for themselves, for the city and for those who need to move quickly and easily on our roads.
“Between our buses and trams, we have some of the most highly regarded public transport providers in the country.
“We are working closely with Lothian Buses, Edinburgh Trams and other partners to reduce congestion in the city, improve and expand the public transport network and make movement around, and in and out of, the city a positive experience.”