Williams proposed to his girlfriend Ayda Field at the end of last year but has decided not to wed too quickly.
Speaking to the News of the World, Williams's father Pete Conway said: "He isn't planning a wedding.
"He hasn't sat down and worked out a date. He will do it himself when he wants to. He's not taking any pressure from anyone."
He added: "There's no hurry. There is no date. Rob's not rushing into this. It's not by any means worked out. It's if, not when, with this wedding."
> Robbie Williams 'delays wedding again'