La Liga leaders Barcelona struck the agreement to finally sign Coutinho on Saturday afternoon and he quickly jetted to Spain to complete proceedings.
Both clubs have now announced the deal but Coutinho must still go through the formalities of the medical and agree personal terms.
But there is not expected to be any issues with either and he will be officially unveiled today.
Marca have suggested he will sign the contract today alongside president Josep Bartomeu before the unveiling at the Nou Camp and a press conference.
But Coutinho has already spoken Barcelona’s in house TV company.
“I’m very happy, very happy,” Coutinho, who watched Barcelona’s 3-0 league victory over Levante at the Nou Camp, told Barca TV.
“I have always said that it is a dream that I am living and I am very happy to be here.
“To be able to play, win titles, make the fans happy… always play with joy. It is incredible to know that I am going to live with idols, players with a lot of history.
“Footballers like Leo Messi, Luis Suarez, (Andres) Iniesta, (Gerard) Pique, (Sergio) Busquets. I am very happy to be able to live together, to be able to learn from them and be able to win together.”
Coutinho will sign a five-and-a-half year deal and become the world’s second-most expensive player.
The 25-year-old watched Barcelona’s 3-0 win over Levante at the Nou Camp on Sunday and could make his debut against Celta Vigo on Thursday.
Barca had targeted Coutinho in the summer but saw three bids rejected by Liverpool even after he had submitted a transfer request but they decided to come back in for him this month.
And Coutinho managed to finally get his dream move after making it clear to Liverpool and Jurgen Klopp his heart was set.