The Barcelona midfielder believes any further attempts by the club to tempt the shot-stopper into extending his stay at Camp Nou is a "waste of time"
Valdes, 31, has said that his 11-year spell with the Blaugrana is drawing to a close after declining the opportunity to prolong his time in Catalunya beyond the expiration of his current deal in June.
And Iniesta, whose emergence at Camp Nou coincided with that of the shot-stopper in 2002, believes the club are powerless to prevent him from leaving.
"It is not a matter of convincing Valdes now," the 29-year-old told El Larguero. "He made his decision and I think all of this talk [of a possible stay] is a waste of time.
"He has already explained his reasons and we must respect his decision."
The Spain ace, whose representatives are said to be negotiating a new contract to extend his stint with the Catalans, has said that finances will not play a major role in his decision to sign a new deal.
"Barca is my family," he added. "For me it does not matter if I'm second, third or fourth place in the club. I just want them to feel the same about me as I feel about them.
"There are other things more important than money. If I wanted to leave I might see things differently, but when the time comes to renew my deal I will."