"Jack's going nowhere. People are aware of him - and they have been for a long time," Hughes was quoted as saying by British media.
"Do I think that's a fair value? No. We wouldn't place a value on him," Hughes said, when asked about the 20 million pound valuation.
Butland, who begun his career with Birmingham City, was a surprise inclusion in England's squad for Euro 2012, although he did not make an appearance in the tournament.
Hughes praised the goalkeeper's rise but warned he should be focused on cementing his place in Stoke's starting eleven.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
"Jack forced his way into the England squad when he was 19 He's had a great career progression, every step he's taken he's dealt with. Now it's about consolidating himself in a very good Premier League team. That's the challenge for him," Hughes said.
The Potters, who are 12th in the Premier League table, will rely on Butland to keep out a formidable Manchester City attack when they host the league leaders on Saturday.
(Reporting by Shravanth Vijayakumar in Bengaluru. Editing by Patrick Johnston)
