Eto'o came through successfully his medical at Appiano Gentile yesterday.
The Nerazzurri's new striker was largely expected to sign tonight and put pen to paper on a five-year deal which will keep him at San Siro until 2014.
"I very happy to be at Inter. I am here to work and win the Champions League. I complement my new team-mates, who have already won the first derby of the season," Eto'o said referring to the Nerazzurri's 2-0 victory over Milan in the World Football Challenge last night.
"After 13 years in Spain, today is the start of a new adventure for me. I would like to once again thank President Massimo Moratti who is a person of great heart and was an important reason why I came here to Inter. I hope to repay him with work on the pitch.
"Now it's important to rediscover my fitness and join the team so we can work together."