Cycling Weekly has learned that the UCI wrote to Lance Armstrong on two separate occasions to explain that he would not be eligible to ride the Tour Down Under before the American announced his intention to make it his comeback race.
Last week Armstrong said he would make his competitive return at the Australian race, but that plan appeared in jeopardy when the UCI revealed that he may not be eligible because of a rule that states riders returning from retirement must give six months' notice.
A source at the UCI said: "He didn't stumble across the rule. The rule was conveyed to him very clearly in two letters."
The UCI source said: "This is a very difficult situation for us. We spent two hours in very heated debate, with people on both sides of the argument.
"It seems to us at the moment a no-win situation. If we say he can't ride because of this rule will we have the big donations to the cancer charity withdrawn? Will we be seen as bureaucratic and nasty and unsupportive to his cancer foundation.? And we could potentially lose a significant non-European event to the calendar if we enforce this rule.
"Or we say 'no you can't ride'.
"It's not a mandatory part of the anti-doping code. It's a discretionary rule and a very difficult one to apply because often we don't know when riders have decided to retire, or when they are coming back."
There is a recent precedent. Mario Cipollini, the Italian, returned at the Tour of California this year for Rock Racing without giving six months' notice. As Armstrong said: "We're not asking for any exception, but they don't always apply this rule.
"This rule was not applied to that. It's a tricky situation. You're talking about a few days overlap."
But the UCI source said: "With Cipollini, we didn't know. Cipollini just arrived on the start line.
"With regard to Armstrong, we are still collecting information from WADA [World Anti-Doping Agency], USADA and USOC [the US anti-doping agency and US Olympic Committee] as to what their views are.
"There is some argument that because this is for a cause and not a person maybe we can be a bit more lenient."
Cycling Weekly contacted Lance Armstrong's representatives for a comment, but received no reply before filing this article.
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