The billionaire sportswear magnate put the north-east giants on the market three months ago in response to mass protests against his regime following Kevin Keegan's controversial departure as manager.
Ashley has even stayed away from St James' Park for fear of his own safety but has now called for a united front and wants to press ahead with his own plans for the Tyneside outfit.
Ashley said in a statement on the club's official website: "I am happy to end the uncertainty the fans may have had about the future direction of Newcastle United.
"I know just how important that is to you.
"I have withdrawn Newcastle United from the market, and for me 2009 will be the year in which we drive the club forward together.
"Even when I haven't been at games I have remained a keen supporter, kicking and heading every ball and cheering the team on TV and being first to congratulate (manager) Joe (Kinnear) whenever there's a good result."
He added: "When I took the decision to put the club up for sale in September I made a point of saying two things were very important.
"Firstly any potential buyer would have to show they had the best interests of Newcastle United at heart and had both the commitment and finance to be worthy custodians of such a fine football club before I would even consider doing a deal.
"And secondly, I gave you my word that as long as I remain owner, this club would continue to be run responsibly at all levels. I hope you will accept that I have stood by that pledge."