Smoke blankets parts of Sydney and Wollongong

Sydney and Wollongong residents are being reassured the smoke blanketing parts of the city is from controlled hazard reduction burning.

NSW firefighters are undertaking a number of hazard reduction burns across the state while conditions are favourable.

Those close to the Ku-ring-gai, Northern Beaches and Sutherland will see the most smoke.

Smoke from hazard reduction burns currently blanketing parts of Sydney. This will clear as the day warms up. #NSWRFS pic.twitter.com/JMlbBjYkiM

— NSW RFS (@NSWRFS) October 20, 2016

Authorities are advising residents to not panic about the smoke, but to report any unattended fires by calling 000.