Ashbee was linked with a switch to Preston on Friday as part of a loan move that would see him reunite with former Tigers boss Phil Brown.
And manager Pearson - speaking after his team's 0-0 draw at home to QPR - said he was "disappointed" by the development.
Ashbee, a Hull servant of nine years, was left out of the matchday squad following the surprise revelation and the City boss told reporters: "I'll give you the facts as they are. (On Friday) He came in and before training, told me a club had offered him a contract - make of that what you will.
"In the afternoon, we had a written transfer request. Apart from that, I'm not making any more statements on that situation.
"Those are the facts as they are. I'll see how that one develops."