Iago tells Othello that Desdemona gave the handkerchief to Cassio. It is true that Cassio has the handkerchief, but it is not true that she gave it to him. Iago tried very hard to that Othello could diverce Desdemona but it didn’t work out.As Roderego said “Tush! never tell me; I take it much unkindly. That thou, Iago, who hast had my purse.As if the strings were thine, shouldst know of this (Parker)”. While Cassio and Iago was discussing about Othello secretly marries Desdemona Cassio start blame Iago for not letting Othello know if Roderigo was in love or loves Desdemona while Iago is Othello’s first chief officers .even though I ago did not really care because he had his own plans that no one could understand except him. Next when Roderigo
