"There was interest from other big clubs but when West Ham showed their interest, it felt like the right move for me and a chance to come and play in the Premier League," he said.
"Of course I know a lot about the manager and also the player he was. He says it is a fantastic opportunity for me to come and play under him and I am very excited about this.
"I am delighted to be here. West Ham is a beautiful club and I am happy that I have signed and can't wait to play."