UPDATE: The road reopened at 8.45pm.

READ MORE: Man dies after car found 'down a steep bank' off A303 near Amesbury

A 'SERIOUS RTC' is currently blocking the A303 between the junction with the A338 and Solstice Park - and it is not known when the road will reopen.

Wiltshire Police says the incident involved a single vehicle on the westbound carriageway, which is currently closed.

A spokesperson for Highways England said: "The A303 is currently closed from its junction with the A338 (Cholderton) to the A345 (Amesbury) with delays of at least 15 minutes covering several miles of the westbound carriageway. 

"This closure is due to a road traffic collision involving two verhicles and Highways England has resources deployed working to restore normal conditions as soon as possible."

However, some drivers say they have been stuck for just under an hour. 

Earlier in the day, Wiltshire Police said that officers were called out at around 4pm to the scene.

Highways England said "trapped traffic" is being turned away from the area.

The eastbound carriageway remains open.

DIVERSION ROUTES

For diversion routes, Highways England said: "Diversion route details and guidance is as follows: Solid diamond symbol.

"Exit at the A338 and travel south towards Salisbury, at West Gomeldon continue straight on to the Portway.

"At the A345 roundabout take the second exit and travel north, continue to re-join the A303."