There are currently "long delays" on the A428 Cambridge Road, eastbound at Caxton.
Queues of around 6 miles are reaching St Neots. The long delays are due to ongoing works by National Highways on the A1198 at Papworth Everard.
Cambridgeshire Traffic and Travel have advised motorists "allow extra time for their journey."
There has been no confirmation of when traffic and road conditions will return to normal.
For the most up-to-date information about the county's roads, visit our LIVE Cambridgeshire traffic map.
Join our Cambridgeshire Travel Information group on Facebook for all the latest traffic news in Cambridgeshire.
Do you have a live or breaking news story from across Cambridgeshire? Email: cambslivenews@archant.co.uk
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