Smokers will find it harder to light up on the streets of North Sydney, after the local council backed a proposal to ban smoking in the CBD.

North Sydney councillors unanimously supported the call to ban smoking throughout public places in the CBD at a meeting on Monday night.

Public smoking will be banned in North Sydney's CBD.

But the mayor of North Sydney, Jilly Gibson, said smokers who flout the rules will not cop fines - at least until the council reviews next March whether the self-regulated ban is working.

Cr Gibson put forward the proposal last year in a bid to make North Sydney one of the first smoke-free business districts in Australia. The commercial hub attracts about 60,000 workers each day.