Tour de France champion Cadel Evans is holding out hope that his adopted son Robel can be with him at the London Olympics.

Evans' wife Chiara revealed on Thursday that British authorities had said it would take three weeks to process a visa for their Ethiopian-born toddler to visit the United Kingdom.

She described the situation as "ridiculous".

But Evans said before Friday's sixth stage of the Tour that they had not given up on gaining permission for Chiara to take Robel to London.

Evans will compete in the road race and individual time trial in the first few days of the Olympics.

"There are just so many rules in the world, our lives are already so complicated, we have to obey rules in maybe five or six different countries," he said of the adoption.

"Some simple things just seem impossible.

"We'll still try to find a way there, for a little guy to go to an Olympic Games.