City pipped the Reds by a point to claim the Premier League title, finishing on 98 points after Sunday's win over Brighton.
It was a title race that will be remembered for years, and Robertson was full of praise for Liverpool's rivals.
"It's obviously a [feeling of] disappointment but also one of pride because we've had a fantastic season," he told Sky Sports News.
"We've come up against a fantastic team and we cannot deny that. Man City are world class and the way they have gone about their business this season, now we can say it, it has probably been a joy to watch.
"They know that we are here and hopefully we are here to stay now.
"Last season they won it by god only knows how many points and now we have taken them down to the final day.
"Both of us have had an unbelievable tally so all credit goes to them.
"Hopefully we can use this. We'll win the league one of these years."