Transport for London (TfL) plans to replace safety-critical joints on the A40 near the Westway roundabout, with work expected to continue until July 2026.
No eastbound access from the roundabout to the Marylebone Flyover will be available during weekend closures, which will run from 10pm on Fridays until 5am on Mondays.
Signed diversions will be in place throughout the works.
A spokesperson said: “The A40 is one of the busiest routes on the TfL’s road network.
“We need to do this work to make sure the A40 Westway can continue to operate safely.”
Drivers are advised to expect serious disruption, particularly during rush hour from 6.30am to 9.30am and 4pm to 7pm, when surrounding roads such as Westbourne Bridge Road will be heavily congested.
Public transport users are also likely to experience delays, especially on bus routes operating on or around the A40 and Westway Flyover.
There will not be any impact on Tube, rail or other TfL services.
TfL is encouraging people to use public transport, cycle or walk where possible.
Alternative driving routes out of London include the A312 Parkway and the A406 North Circular.
TfL has reassured the public that Westfield White City will remain open throughout the works, although journeys to the shopping centre by road will take longer due to increased traffic.
The public is encouraged to use nearby Tube stations, including Shepherd’s Bush (Central and Mildmay lines) and Wood Lane (Circle and Hammersmith & City lines).
Buses also serve the shopping centre, and there are Santander Cycles docking stations in Shepherd’s Bush and White City.
Many nearby areas are within a 30-minute cycle from White City, including Hammersmith in nine minutes, Harlesden in 17 minutes, Earls Court in 18 minutes and Paddington in 21 minutes.
While Westfield will remain accessible by car, roads in the area are expected to be busier than usual, resulting in extended journey times.
