Two teenage boys accused of deliberately lighting Sydney bushfire

Two teenagers are accused of deliberately lighting a bushfire in Sydney's southwest, days after out-of-control blazes destroyed dozens of NSW homes.

The 14-year-old boys were arrested on Sunday afternoon after a fire spread to bushland in Fairfax Reserve at Harrington Park.

Police said the blaze began when a couch was set alight in an area subject to a fire ban.

Local residents were able to douse the flames.

The teenagers were each charged with intentionally causing fire and being reckless as to its spread.

They are due to appear in a children's court on March 14.

The arrests come with the Insurance Council estimating the damage bill from bushfires that raged across parts of NSW last weekend and near Canberra on Friday at $28.5 million.

More than 50 homes were destroyed in the blazes.