Commutes in west London are getting slower with speeds on some roads forcing motorists to crawl through traffic.

Figures from the Department for Transport (DfT) revealed some roads, particularly in Hammersmith and Fulham and Hounslow , saw speeds down by more than 30% since last year.

The worst culprit was the A217 southbound in Hammersmith and Fulham during the morning rush hour which saw the biggest decline to speeds of just 7mph on average in the 12 months to September 2015 - a whopping drop of 35.8% compared to 10.9mph in the year to September 2014.

The next biggest drop was the A406 southbound in Hounslow where speeds were down by 32.4% to just to 11.5mph, year-on-year.

The average speed on west London's A roads during rush hour was 14.6mph in the year to September 2015 - a slight decrease on the average of 15.2mph for the previous year.

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The DfT data also showed the 10 slowest A roads in west London during rush hour over the same 12 month period saw motorists travelling at sluggish speeds between 3.7mph to 6.8mph.

The worst offenders were the A400 northbound in Westminster where average speeds reached just 3.7mph, followed by the A306 eastbound in Hammersmith and Fulham at 4.5mph and the A4007 eastbound in Hillingdon at 5.4mph.

In year ending September 2015, average speeds on A roads in England during the weekday morning peak were 23.6mph.

The DfT said the fall in average speeds observed in recent years is likely to be partly due to increases in traffic levels on the A road network over the same period and that intermittent periods of high rainfall may also help to explain some of the observed decreases in speed.

TEN ROADS WITH THE BIGGEST DROP IN SPEEDS IN YEAR TO SEPTEMBER

Road // Local Authority // Average speed 2015 // % Change on 2014

A217 Southbound // Hammersmith and Fulham // 7 mph // -35.8%

A406 Southbound // Hounslow // 11.5 mph // -32.4%

A3000 Eastbound // Hounslow // 8.1 mph // -27.0%

A306 Eastbound // Hammersmith and Fulham // 4.5 mph // -22.4%

A4209 Northbound // Westminster // 10 mph // -21.9%

A4007 Eastbound // Hillingdon // 5.4 mph // -21.7%

A244 Northbound // Hounslow // 8.2 mph // -21.2%

A244 Southbound // Hounslow // 10.3 mph // -20.2%

A316 Northbound // Hounslow // 13.2 mph // -19.5%

A40 Westbound // Hammersmith and Fulham // 16.2 mph // -19.4%

TEN SLOWEST ROADS LOCALLY IN YEAR TO SEPTEMBER

Road // Local Authority // Average speed 2015 // % Change on 2014

A400 Northbound // Westminster // 3.7 mph // -15.9%

A306 Eastbound // Hammersmith and Fulham // 4.5 mph // -22.4%

A4007 Eastbound // Hillingdon // 5.4 mph // -21.7%

A308 Eastbound // Hammersmith and Fulham // 5.7 mph // -10.9%

A3211 Southbound // Westminster // 6.1 mph // -14.1%

A41 Southbound // Westminster // 6.2 mph // -17.3%

A4201 Southbound // Westminster // 6.4 mph // -4.5%

A400 Southbound // Westminster // 6.5 mph // -15.6%

A3218 Eastbound // Kensington and Chelsea // 6.7 mph // -2.9%

A315 Eastbound // Hammersmith and Fulham // 6.8 mph // -12.8%