Vieira: Gunners need to act fast
Van Persie's 30 Barclays Premier League goals helped propel the Gunners back up into third place and secure Champions League football but the 28-year-old Dutchman has not yet signed a contract extension to a deal which runs out in 12 months' time.
Cesc Fabregas and Samir Nasri were both sold last summer, and Vieira, speaking at the launch of ITV Sport's coverage of Euro 2012, said: "Losing Samir Nasri and Cesc Fabregas last year was a big shock for Arsenal. If they lose Robin Van Persie this year it will be a drama."
He went on: "With Samir and Cesc you can say 'okay those two are gone', but behind you know that there is Jack Wilshere and Van Persie still at the club - but if Robin comes to leave, that means next year it may be Theo Walcott, then the next year is it going to be Wilshere? It is going to be difficult for Arsenal to keep the top players.
"On the other side if they keep Robin they are going to send a positive message to all the clubs and to all the people around and I think it's really important to keep him."
Vieira, who won three Premier League titles and the FA Cup four times while at Arsenal and is now football development executive at Manchester City, continued: "From Arsenal's point of view, I think that is something they should have closed a long time ago, but Arsenal don't need me to tell them that.
"That is the way it is and they will have to deal with it.
"It is a big risk because they lost Samir and Cesc last year. You never know and will have to wait and see what happens."
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