The 29-year-old England international has scored 12 goals in 21 appearances for the Blades since his £4million move from Everton, despite Robson's side struggling to mount a promotion challenge.
"Nobody has come in and offered anything for James Beattie," Robson told Sky Sports News.
"As far as I'm concerned he's had a good time at Sheffield United, he's scoring goals and working hard up front. So as far as I'm concerned he'll be staying at the club."
Middlesbrough are rumoured to be the main suitors for Beattie if the Bramall Lane club did decide to cash in in the new year.