Armstrong had been invited by the organisers as a keynote speaker at a new business related event ahead of the 1 April race.
The invitation to Armstrong by Tour of Flanders boss Wouter Vanderhaute led to a protest by International Cycling Union president David Lappartient who said he would not attend the race if Armstrong was present in any capacity.
"I can't confiscate the American’s passport and prevent him from coming to Belgium," Lappartient told Het Nieuwsblad in January.
"I understand that he could be invited as a conference speaker, and he will obviously attract a lot of attention, but this is not the image that we want to send out from cycling. We want to promote a clean sport, and Armstrong is not the symbol of that."