The midfielder is emerging as a key target for new United boss Erik ten Hag.
The two worked together at Ajax, before de Jong left to join Barca.
The Catalan giants have financial issues and want to raise around £70 million by selling de Jong.
He said on international duty on Tuesday: "You're always flattered when teams show interest in you as a player.
"But, as you say, I am at the biggest club in the world at the moment and I feel fine there, so no news."