The 29-year-old defender/midfielder has been quoted as saying that the deal is in place for him to come to West Ham and it will be completed very soon.
According to Spartak Moscow player, he will join up initially on loan until the end of the season with an option to buy if things go well.
"West Ham's manager and executives want me," said Kovac.
"West Ham love Czechs, they already have Jan Lastuvka and Marek Stech in their squad.
"This year I will be 30 and I only have a few years left before I become known as a veteran, so I want to realise my dream of playing in one of the main championships.
"Everything happened on Wednesday, my agents recently started to actively work and they found a few options, but I never really thought my pre-season with Spartak now would be my last one.
"I haven't even had chance to say goodbye to my team-mates, but I have had a call to say everything is ready and my ticket to