Pep Guardiola says Manchester City have to win the Champions League to be "considered one of the best teams".
City, whose only European title is the 1970 Cup Winners' Cup, play Italian side Inter Milan in the Champions League final next month.
They lifted the Premier League trophy for the fifth time in six seasons after their 1-0 win over Chelsea on Sunday.
"You have to win the Champions League to be considered one of the best teams like United or Liverpool," he said.
Speaking to Sky Sports, Guardiola added: "But also it's unfair to say if you don't win it, the Premier League doesn't make sense.
"Of course it makes sense, of course it's important. It's every day, every week. This club won five of the last six but six of the last 10 and seven of the last 12. It's amazing."
Defender Kyle Walker says City "are not finished" as they target the Treble, with an FA Cup final against rivals Manchester United also to come.
"We will celebrate tonight and then move on to try and create history," Walker told Sky Sports.
"We always believed we could do this. This group of lads are professionals and winners.
"Rest assured we are not finished. We have the FA Cup against our bitter rivals and then the Champions League.
"The treble would be fantastic but there is a lot of football to be played. To say we are up there with one of the greatest Premier League teams of all time we have to conquer some of that.
"To go and achieve that we could then start talking about being one of the greatest teams in the Premier League."
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'We feel unstoppable'
City midfielder Jack Grealish, who has now won back-to-back Premier League titles since joining from Aston Villa in 2021, told Sky Sports: "Last season was nice because it was the first one but this year it is so nice as I feel I have played more of a part.
"It is mad. I spoke to some of the lads not a while ago and said 'imagine you have to win 12 games in a row to win the league'. We have so much talent and we feel unstoppable.
"I feel so much more confident in this team. I feel fitter and back to what I know, what I can do. This is why Man City bought me and I have so much to offer.
"It doesn't stop yet, we still have some massive games left."
Defender John Stones, who has thrived in a more advanced midfield role in recent weeks, said: "It is surreal thinking this is my fifth Premier League title. This one has been so enjoyable. The way we have played different roles."
Belgium midfielder Kevin de Bruyne, who has also now won five Premier League titles, said: "You work 11 months to see this. It is a day to celebrate with the fans and the family. It is amazing.
"I have been here eight years. This is my home and the amazing moments keep on coming."
Erling Haaland, who has scored a remarkable 52 goals in 49 games in all competitions - including a record-breaking 36 goals in 34 Premier League matches, added: "It is unreal. I don't know what to say. I am so happy. These are the memories I will remember for the rest of my life.
"Debut season, 36 goals, Premier League trophy and two more finals to come. Not bad."
Kalvin Phillips says he "enjoyed every moment" of his first Premier League start for the club, but admits he has been low on confidence this season after struggling for regular action since his £45m move from Leeds.
"It was a great feeling. I was happy because we won the league and I knew there might be a chance I could play. I have enjoyed every moment," he told Sky Sports.
"It has been unbelievably tough this season and probably the lowest point confidence-wise in my career. But Kyle Walker and the guys have kept me going and told me I would get my chance."
Walker backed his City and England team-mate to add more titles to his collection.
"Kalvin has won one now and he will win plenty more," said the 32-year-old. "One of the nicest guys I have ever met in football.
"He deserves the Premier League and it takes a while to settle in but he has shown his quality."
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