"I feel fine, thanks, not bad. It's a beautiful day," Le Pen said on Monday when arriving to the headquarters of his party.
Le Pen faces a disciplinary hearing for his reiterated comments last month about World War II.
"Jean-Marie Le Pen should no longer be able to talk in the name of the Front National, his comments are against the fixed (party) line," his daughter Marine Le Pen and Front National chief told French radio on Sunday.
During the traditional 1 May rally on Friday, Le Pen unexpectedly came to the stage to take the ovation of the crowd following his daughter's speech.
"I have the feeling he can't stand the fact that the Front National still continues to exist without him in charge," said Marine Le Pen.
Last month her father agreed to stand down in regional elections but insisted he would not quit politics and would continue as a member of the European Parliament.
Since succeeding her father as party chief in 2011, Marine Le Pen has tried to distance the party from its racist image as she plans to bid for the next French presidential elections in 2017.