Queensland Reds coaching director Ewen McKenzie said Tuesday he will quit at the end of the Super Rugby season, with reports linking him with the Wallabies or a Six Nations side.
McKenzie, who joined the Reds in 2009, guided the franchise to its first championship in 2011 in addition to back-to-back Australian conference titles and is widely seen as one of the best coaches in the world.
He said he wanted to pursue new challenges and was making the announcement now to provide clarity to the club and its players about the future.
"My experience at the Reds and with Queensland Rugby will be something I'll always treasure but I feel the time is right to pursue new coaching challenges outside of Super Rugby," he said on the Reds website.
"Anyone who knows me understands I have strong coaching ambitions and, after spending nine years coaching at a Super Rugby level, I'm excited about pursuing a different role either here or overseas.
"Knowing that the (Reds) rugby programme is in a position of strength for the future does make the decision slightly easier as you know the culture and structures are in the right place," he added.
McKenzie has long been seen as a potential successor to Wallabies coach Robbie Deans, whose is contracted till the end of the year but could be axed early if they fail badly against the British and Irish Lions in June-July.
But ACT Brumbies coach Jake White is also seen as in contention and reports said that if the Wallabies job eludes him he will almost certainly be offered a head coaching position with a Six Nations side.
"Indeed, the worry for Australia is that another country, with Ireland the leading contender, will snap him up as head coach before the Wallabies position is even put up for grabs," The Australian newspaper's rugby writer Wayne Smith said.
Queensland Rugby chairman Rod McCall, who was responsible for the appointment of McKenzie, said his departure would be a huge loss.
"When Ewen joined us in late 2009 the Reds and Queensland Rugby were at a very low point," McCall said.
"Over the past four years, Ewen has not only been responsible for turning around the on field performances and attitude of the Queensland Reds, but he has also played an integral role in bringing success back into our organisation and to our wider code in Queensland."