Guardiola is said to be Blues owner Roman Abramovich's number one target to succeed Andre Villas-Boas as manager, with reports suggesting he could be offered a £10million-a-year contract.
But the 41-year-old gave short shrift to questions about whether he would swap the Nou Camp for Stamford Bridge, claiming Chelsea already had a "very, very good manager" in caretaker Roberto Di Matteo.
Guardiola, who has still to sign a new contract at Barca to replace the one that expires this summer, said: "It is fantasy, it's hypothetical.
"I am coach of Barcelona now and they have a good manager who is getting unbelievable results.
"It's not useful for Chelsea or for Barcelona to talk about that. There is no time to talk about that."
Guardiola has been asked countless times this season whether he will stay on at Barca and it was no different on Tuesday night.
He replied: "I just want to focus on the game. This is a dream come true, to be here ahead of this great game.
"I just want to make sure my players are focused on the game and can enjoy playing matches like that."
That game is Wednesday's Champions League semi-final first leg at Stamford Bridge, the latest instalment in a Chelsea-Barca rivalry that has become a saga.
The build-up has been dominated by talk of revenge, with the Blues still smarting from the sides' last meeting in 2009.
That saw Chelsea denied several penalties before Andres Iniesta's stoppage-time away goal saw Barcelona triumph.
Guardiola said: "A long time has passed. I don't think they are playing for revenge.
"What you have lost, is lost. We will both be playing to try to reach the final in Munich."
Barca emerged from that triumph to establish themselves as one of the greatest - if not the greatest - club side ever to play the game.
Guardiola, who recalled his euphoric celebrations that night, said: "That was our first year together.
"We had that kind of love story you have in the first year.
"We were united, and we scored that goal right at the end. The rest is history."
While Barca have gone on to conquer the world since 2009, Chelsea have endured a turbulent three years that brought them their first ever double but more Champions League misery.
They looked certain to suffer the same fate this season before Andre Villas-Boas' sacking just over six weeks ago but they are a side reborn under Roberto Di Matteo.
Di Matteo has had a near-identical impact to Guus Hiddink three years ago and Guardiola said: "They have the same spirit, the same soul, the same foundation.
"They've changed the manager and a couple of players, but the same players are largely there.
"I do admire that generation of players, who have done so well over the last seven years and have got into so many semi-finals and finals, and competed in the Premier League so well."