Spot fires were still burning about four kilometres from the southern ACT border were located near the remote area of the Namadgi National Park on Sunday afternoon.
The ACT Emergency Services Agency said there was no threat to homes within the ACT and it would continue to monitor the situation in NSW.
"The ACT is well resourced and is on high alert to respond to a bush or grass fire in the territory," it said in a statement about 1pm.
Earlier, it said the announcement was very early notice to the rural land holders within the remote areas of the Namadgi National Park.
"The nearest rural residential property is 25 kilometres from the current fire activity," the agency said in a statement about 7.20pm on Saturday.
"Firefighters are currently on scene preparing to protect historical assets if required.
"Naas Road from the Namadgi Visitor Centre is closed southbound until further notice. Access will be provided to residents and emergency vehicles."
Two small grassfires - one on Kent Street in Deakin, and the other near the Woden Cemetery - were extinguished by firefighters on Saturday evening. The causes will be investigated.
Thick smoke from the NSW fires also blanketed the capital, to an even greater extent than what Canberrans had become used to over the previous weeks.
Temperatures in Canberra did not fall below 40 degrees until after 7pm, as north-north-westerly winds came through the city, gusting about 50 kilometres an hour at 7pm.
