World number one Federer and Russian Safin, who beat the Swiss at the semi-final stage en route to winning the 2005 Australian Open, head the line-up for the select eight-man field at the Jan. 10-13 event.
Joining them will be defending champion Andy Roddick of the U.S., Argentina's David Nalbandian, Czech Radek Stepanek, Germany's Tommy Haas, Croatia's Ivan Ljubicic and British teenager Andy Murray.
A knee injury prevented Safin from defending his Australian Open crown in 2006 and the Russian, a former world number one who slipped to 104th in August, will be playing Down Under for the first time since defeating Lleyton Hewitt in the 2005 final.
Stepanek and Murray, the world's 14th and 17th-ranked players, will make their debuts in the round-robin tournament.
Of the world's top-five players only Spain's number two Rafael Nadal, who is playing in the Sydney International, will be missing from the Kooyong field.
The 2007 Australian Open runs from Jan. 15-28.
