He told The Sun: “I miss Champions League football.
“When I’m at home in the week watching the Champions League on TV and hear that music it makes me realise that there’s a part of my football make-up that is missing.
“The challenge of being part of the best, playing against the best.
“Champions League football means everything to any footballer with ambitions.
“I’ve enjoyed playing for Blackburn — and the manager and his staff are first-class. The club is really friendly and professional.
“But at 29 years old, if a club like Chelsea comes looking for you then you must seriously consider the opportunity.
“Not necessarily from a financial perspective but from a point of view where you can win trophies and compete against the AC Milans and Barcelonas of this world. I can only talk about things that are certain, not about maybes.
“But a chance to go to Chelsea — or any other Champions League team in England or Spain — would be hard to turn down.
“Blackburn gave me my chance and even though it was not a big transfer fee, I trust that I have already paid them back with my commitment and goals this season.
“If I end up being sold by Blackburn and they make a good profit, fantastic, they deserve it.
“The people at the club and the fans are great.”
He added: “Mourinho has coached me. We won things together and he really knows me inside out.
“If he ever were to sign me again, it would be because he knows exactly what he’s getting and that I’ve managed to settle down in England quite quickly.
“It would be a big challenge to win a regular start in a club like Chelsea but why shouldn’t I have confidence in my own abilities? I know I can compete with the best.”