Ferries halted as heavy fog descends on Sydney Harbour

Sydney Harbour Ferries were cancelled this morning and motorists were warned to drive with caution after a thick layer of fog descended on parts of the city.

Footage from the 9NEWS chopper showed the flags atop the Sydney Harbour Bridge peeking through the fog, which was forecast to be thickest around Campbelltown, Richmond, Liverpool and Penrith.

The Transport Management Service issued a warning for motorists travelling between Somersby and Mt White on the M1 and areas surrounding Eastern Creek on the M4.

“We are issuing a general warning for people to exercise caution, keep their head lights on and take it easy on the roads,” a TMS spokeswoman said.

Do you have any photos of the fog? Send them to contact@9news.com.au