The two clubs are understood to be on the verge of agreeing a £3.5 million fee for the England Under-21 international. Villa rejected an initial bid for Gardner and any add-ons relating to the deal have still to be thrashed out.
Pannu said: "Our offer for Craig Gardner is still on the table and we are pretty close to a deal."
Gardner has come through the academy ranks at Villa but recognises the need to play first-team football at this stage of his career.
He has slipped further down the Villa pecking order this season after the arrival of Fabian Delph from Leeds and also has James Milner, Stewart Downing, Ashley Young, Nigel Reo-Coker, Steve Sidwell and Stiliyan Petrov ahead of him.
Gardner could become Blues boss Alex McLeish's second January signing after Sporting Gijon playmaker Michel.
He also wants to sign a striker with Liverpool's Ryan Babel still on his radar although attempts to sign Sunderland's Kenwyne Jones have floundered.
Blues striker Marcus Bent has returned to the club after a two-and-a-half-month loan spell at Middlesbrough.
Bent will now provide back-up for Cameron Jerome, Christian Benitez and veteran Kevin Phillips.