The 28-year-old defender has been linked with Tottenham after a strong 2020/21 season.
Asked about Vestergaard's future, Hasenhuttl told BBC Radio Solent: "The situation is that he is back on Monday.
"He has one year left on his contract, I plan with him next season, definitely. We need everybody here. He played a very good Euros.
"It wouldn't be surprising if there were offers coming. But I plan with him next season."
Need a VPN? Or seeking to switch? Then support Tribal Football by clicking here to sign up with our official partners NordVPN. Not only will you receive the best VPN experience, but also great discounts by signing up via Tribal Football. Thanks for your support!