A multi-vehicle accident near the M5 East tunnel is causing lengthy delays for motorists travelling into the city on Tuesday morning.
The crash, just before 6am on the approach to the tunnel at Kingsgrove, resulted in the closure of both citybound bound lanes for at least 30 minutes as emergency services and traffic crews responded to the incident.
A breakdown lane was used to move vehicles slowly past the accident site.
Both lanes have since reopened but the onset of regular peak-hour traffic has combined with the already backed-up traffic to produce significant delays.
Just after 7am, traffic stretched about six kilometres up to Fairford Road, but was "starting to slowly improve", Transport Management Centre spokesman Dave Wright said.
"Anyone who is heading into the city via the M5 East or anyone who is heading to the airport needs to factor in plenty of additional travel time," he said.