Reports emerged on Friday that the Tynesiders were attempting to push through a deal for the World Cup winner, with representatives of the player and Brazilian club Atletico Paranaense believed to be in Newcastle to agree terms.
However, Robson does not believe he will add the Brazilian`s signature to those of Jonathan Woodgate and Tony Caig.
Asked to comment on the possibility of other players coming in, Robson said: "Not that I know of."
Commenting directly on the Kleberson reports, he added: "I wouldn't know one way or another, I have been far too busy to consider the Kleberson deal.
"As far as I am aware, we made an offer, which was rejected, end of story."
Robson did admit, though, that they always have one eye on the market, saying: "There is never ever a complete jigsaw.
"You are always looking to improve, but I am very, very happy with the squad that I have got.
"I think we have an exquisite squad, one that is capable of challenging Arsenal and Manchester United."
It is believed that a deal could be struck to bring the defensive-minded midfielder to St James` Park in the summer.
