The 21-year-old had an impressive campaign on loan at the One Call Stadium last season and Clough said Stags will keep an eye on him, but any move would be on Mansfield's terms.
“We like Ryan an awful lot and he had a great season,” said Clough.
“It was inevitable he was going to dip a little bit, which he did towards the end of the season, as it was his first full season in league football.
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“But we think he has an awful lot of potential.
“Last time we had a conversation with Birmingham it was a fee involved and a larger one than we would be willing to pay for him.
“He's got a year left at Birmingham we we will just monitor that situation and see how it goes.
“If it happens it will happen on our terms.”