The chief executive of the Professional Footballers' Association Gordon Taylor -- who is seeking a resolution to the dispute -- did not respond to CNN's request for an interview.
When asked if other clubs had expressed an interest in Cisse, Diene couldn't "answer that question."
Earlier he insisted that Cisse "loves the fans, the club and the city."
Cisse played a significant role in helping Newcastle to overachieve and finish fifth in the Premier League in 2011/2012, scoring 13 goals in 14 appearances after joining from Freiburg for $13.7 million during the January transfer window.
But he cooled last term, netting eight league goals as he played second fiddle to Demba Ba. Ba was then sold to Chelsea and Newcastle barely avoided relegation.
The Cisse saga has added to an already lively off-season at Newcastle, one of England's best supported clubs with an average league attendance last season of more than 50,000.
In June, the Magpies rehired the outspoken Joe Kinnear, which did not go down well with the club's fans. Formerly a manager, he was brought back as director of soccer.