The Bulgarian striker has been linked with a move across London to Arsenal in the transfer window and was left out of the Cottagers' FA Cup third round clash with Norwich.
Asked if he was resigned to losing Berbatov, Fulham manager Meulensteen said: "No, I am not resigned to anything.
"You can only resign to something when things happen and at this moment in time it hasn't. He is a Fulham player and a very important one for us.
"We would lose quality, experience, that special aspect that makes him stand out from the others.
"He can do things, turn things on, pull things out of the hat. He is an exceptional player."
Costa Rica forward Ruiz, who was signed in 2011 for a fee believed to be in excess of £10m, has been linked with a loan move to Real Betis and a return to Holland.
Meulensteen has used Ruiz just twice since he succeeded Martin Jol, and he said: "We've allowed Bryan to talk to a number of clubs to see if anything can come out of that.
"Don't get me wrong, he's a very good player. I've come in, I've looked at the squad, I've worked with these players.
"I've picked my teams on what I think are the right reasons and motivations and I can also understand Bryan's. He's a good player, he's got a World Cup coming up and he obviously needs to play."
Meulensteen was also quizzed about potential arrivals to Craven Cottage, ruling out a move for Brondby target man Simon Makienok and downplaying reports of interest in West Ham's Ravel Morrison.