The 25-year-old's performances during his 15 Bundesliga appearances this season have caught the attention of many top European clubs, including Liverpool along with the Red Devils.
Zakaria operates in a defensive midfield role, an area of the pitch which Man United interim manager Ralf Rangnick is said to be keen on improving in this mid-season transfer window.
The Swiss international's contract with Gladbach is set to expire at the end of this campaign, and he is believed to be unwilling to sign a new deal amid speculation of a move to Old Trafford, and now Eberl has confirmed that Zakaria is free to leave the club.
Eberl told Kicker: "There's nothing on my desk. It's not surprising that there is speculation about both of them and especially Denis, but it's no longer our topic.
"They both still have a half year of contract. But we have also said again and again that if something comes up that we have to deal with it for financial reasons.
"I cannot rule out that both will leave the club in winter - or one. There will be changes in the summer. We've worked with one squad for almost three years now."
Zakaria joined Gladbach in 2017 and has gone on to score 11 goals in 144 appearances for the club. body check tags ::