The Icelandic midfielder has been impressive since signing for the Swans on loan from Hoffenheim in January.
According to The Mirror Football, Alan Pardew has made discreet enquiries about his availability to his German parent club.
Sigurdsson, 22, has made a huge impact at Swansea despite failing to establish himself in the Bundesliga.
The midfielder could cost around £8million and the Premier League Player of the Month for March has also been attracting interest from former club and newly-promoted side Reading as well as West Ham.
Source: DSG
