The Dutch international is expected to seal a switch to Fred Rutten's side before the transfer window shuts on Monday, with the imminent move angering Ajax fans who are unhappy with his decision to join their club's fiercest rivals.
Vermeer, who has been at Ajax since signing for them as a youth player in 1999, was subjected to a wall of abuse from fans as the Amsterdam-based side went down 2-0 to Groningen over the weekend and has called for calm.
"I know how it is between Ajax and Feyenoord and understand that this transfer will be very painful for some," Vermeer told Dutch newspaper De Telegraaf on Monday.
"But it was a chance I had to grab with both hands. I’m grateful to Ajax for 14 fantastic years but I had to put myself first. I want to be playing. And I can do that at Feyenoord.
"Lets hope everybody uses their right mind."
Ajax coach Frank de Boer expressed his surprise at the move after the match against Groningen, insisting he had no idea Vermeer wanted out.
"Vermeer has almost completed the move. It was a complete surprise to me. I only heard about it on Saturday night. It was a big shock," said De Boer in his post-match press conference.
The reigning Eredivisie champions have wasted little time replacing the 28-year-old, confirming the capture of PEC Zwolle shot-stopper Diederik Boer on Sunday.
Boer has a wealth of experience in the Dutch top flight and is set to serve as understudy to Jasper Cillessen after signing a three-year deal.
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