Huddersfield have told Swansea that midfielder Philip Billing is not for sale.
Swansea made an enquiry for the 6ft 5in Dane as they weigh up options to replace Everton target Gylfi Sigurdsson.
Billing played 28 games last season but coach David Wagner thinks the 21-year-old can have a greater impact in the Premier League next season.
The youngster did receive praise from BBC pundit Alan Shearer after his performance in Huddersfield's 5-1 defeat at Manchester City in the FA Cup.