"How do big clubs improve their teams? With better players. So of course big clubs around the world are going to know his situation," he told UK newspapers.
"When the big, big players go to Barcelona they understand that Lionel Messi is unique.
"But Alexis is just one step below. Alexis is a fantastic player and I'm so happy how he's playing at Arsenal, especially this year scoring goals.
"Put Kevin De Bruyne with one year left on his contract and see how many teams [are interested]."