The organisers of the race in Argentina decided to take action against the 36-year-old Belgian rider for "behaviour that damaged the reputation and honour of the Vuelta a San Juan, the UCI and cycling in general".
He was fined 3000 pesos by local police in Argentina after the woman saw the picture and made an official complaint after speaking to her lawyer.
Keisse finished 29th in the stage three time trial on Tuesday, won by team-mate Julian Alaphilippe, before the decision to expel Keisse was announced before midnight.
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"I am very angry. They disrespected me; I was working, I asked for a photo and they disrespected me. I already spoke with my lawyers to see what we can do. My partner saw the situation and he is a witness,” said the woman.
They cannot come to another country and treat women as things, as something insignificant and worthless. This is Argentina and he cannot come to do what he wants. I hope that at least they sanction him or call his attention for doing what he did.
The woman claimed Keisse brushed against her, but the Giro d'Italia stage winner has denied the allegations while also apologising for his actions.
"I made a mistake – I realise that. It will not happen again. I also want to apologise to everybody – to the Argentinian people, but not only them: to everybody who feels offended by what I did.
"To the race organisation, which has been in difficulty because of this, to my team, actually. I want to apologise to everybody. It was a really stupid thing to do. I wish I could turn back time. but I can't.
"I cannot do more in this moment than say I'm sorry and promise that things like this will never happen again."
A local judge fined Keisse 3000 pesos for his conduct, and warned that such sexist behaviour and attitudes must change.
"Things have to change, be it a French tourist, an Italian or someone from San Juan. Be it a construction worker, engineer or lawyer, things must change," said local judge Enrique Mattar.
"Women have to be able to walk quietly down the street, be happy at work and at home. Things have changed socially. That's enough of sexist jokes and macho attitudes that are no longer socially tolerable."