Manchester - Pep Guardiola says he is refusing to entertain talk of Manchester City's bid to complete an unprecedented quadruple, even if they start the process by beating Chelsea in Sunday's League Cup final.

Victory at Wembley will would put Premier League leaders on course to win four competitions, although City manager Guardiola claims he's not even thinking about the possibility of such a historic achievement.

"Ask me this question in May. In April, May ask me that question and after I will tell you the answer. I will not lie to you," he told reporters on Saturday. 

"Now it is impossible to ask about that. Kevin (De Bruyne) said perfectly the last press conference in Germany (after City's 3-2 Champions League win over Schalke 04) - 'next target, next game'."

Having hammered Maurizio Sarri's troubled Chelsea 6-0 in the league two weeks ago, City will start the final as heavy favourites, but a tight Premier League title race with Liverpool and a host of top teams to get past in the Champions League, Guardiola discounted his side's chances of winning all major four trophies in a single campaign.

"How many times in England, one team wins four titles in one season?" he said.

"Sir Alex Ferguson’s incredible United? He never did it. Liverpool, in the eighties, how many Champions Leagues they have in their pockets? They didn't do it. 

"So don't put the pressure on one team in February or November or December. You have to win four titles - it is impossible. In May we will see.

"That is not fair on us. Try to win the next one and after in April or May we will see how is our position."

United in 1999 remain the only English club to win the widely-accepted definition of a treble - a country's league title and major cup competition plus the Champions League - something Guardiola accomplished with Barcelona a decade later by beating Ferguson's Reds in the Champions League final.

City's hopes of retaining the Premier League title would be boosted on Sunday should their closest title challengers Liverpool lose their game in hand on Sunday - at rejuvenated Manchester United.

But when asked to choose which result he would prefer - a City win over Chelsea or a Liverpool defeat at Old Trafford - Guardiola shot back an instant answer.

"City win! Once we are in the final, it is the most important game in the season," he said.

"Of course it would be good for us if Manchester United take a result but we have a final.

"Maybe for United and Liverpool the League Cup is not important, in their cabinet of trophies, they have many titles, but it is not our case.

"Retaining a title will be good and playing a final will be good and always will help us grow as a club."