It was thought that the two-time World Cup winner would retire from the game after the global showpiece in Japan, with other commitments such as family and his studies now taking up a lot of his time.
But the 33-year-old said he still “had the fire inside him” to play rugby at Test level and would even consider looking into rugby league offers.
“I’ve enjoyed the process so far,” Williams told the Sydney Morning Herald.
“And I have to think about what I will do in the future. I am positioning myself in case that becomes an option. I am enjoying doing a bit of studying and keeping my brain going in a different way.
“The last couple of years have been tough with injury, but I still have the fire inside me. I still feel fresh.
“I’m not sure if league is in my future at 33 but) if there are offers, I will examine it with my family and go from there.”