Federer's wife Mirka was sitting in the players section and he was reportedly upset that Wawrinka had blamed her.
The two were then seen involved in a long and tense discussion in the locker-room after the match and on Monday each went their own way en route from London to Lille in northern France for the Davis Cup showdown.
As it turned out Federer was unable to play in Sunday's final in London as he was laid low with back spasms, casting doubts on his ability to play against the French and win the Davis Cup for the first time in his distinguished career.
There was no fresh news on Federer's injury out of the Swiss camp on Tuesday, but the 17-time major winner did not practice on Monday while Wawrinka did.
Instead, Federer stayed in his hotel room and avoided all contact with the press.
Sunday's withdrawal was only the third walkover of Federer's career and he has never abandoned a game during play.
Widely regarded as being the finest tennis player of all time, Federer has won all there is to win at the top in tennis apart from Olympic singles gold and the Davis Cup.
His greatest rival Rafael Nadal on the other hand has the full set of all four grand slam titles, Olympic singles gold and the Davis Cup.
Federer has blown hot and cold on the Davis Cup over the course of his long career, but with Wawrinka, this year's Australian Open champion, finally emerging as a player of the highest-class, a Davis Cup win has been a priority for him.
-AAP