Australia's Upper-Hunter wine region was put on high alert yesterday after the bush fires across New South Wales were driven to within 3km of Broke.

Cessnock was under threat last night as firefighters battled a huge fire front bursting out of the Yengo National Park into farmland west of the town.

But the township of Broke, north-west of Cessnock, was under extreme threat, the Sydney Morning Herald reported. "Late last night and firefighters were on standby to defend the hamlets of Boree and Wallabadah from a separate fire also coming out of the park," it said.

Micheal Hope of the Hope Estate Winery said in Australia's Daily Telegraph that the fire had crossed containment lines.

Residents who attended a Broke town meeting yesterday where told they may have to evacuate.

"If the winds stay as they are, we are safe…but if the winds change direction then we have to evacuate," Hope said.

Ash and smoke are already coming down onto the vines, and the fear is that if they come over the hill the flames will spread quickly.