Barcelona have made an official approach to Dinamo Zagreb with regards to a summer move for Spain international Dani Olmo, multiple sources have told ESPN.

The Spanish champions have informed Zagreb that they are interested in signing the versatile forward and enquired about a possible price, although they have not made an official bid at this stage.

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Olmo, who came through Barca's La Masia academy before leaving for Croatia in 2014 aged 16, has a contract with Zagreb until 2021.

Barca have been following him intensely in recent months, especially in the Champions League, where he scored two goals in six group games.

Reports in Mundo Deportivo and Diario Sport on Tuesday said a first offer had already been tabled but sources inside the club insisted to ESPN that the first approach was just to ask about the state of play.

Olmo, 21, shone at last summer's U21 European Championship for Spain and has since gone on to make his senior debut. Zagreb placed a €40 million price tag on his head at the time following interest from Juventus, Atletico Madrid, Manchester United and Tottenham.

A few days ago, while back in Catalonia on holiday, Olmo himself suggested his time in Croatia was coming to an end, opening the door to a summer transfer.

ESPN reported in September that Olmo, along with Real Betis right-back Emerson and Napoli midfielder Fabian Ruiz, was one of three players being closely followed by Barca.

However, despite stepping up that interest in recent weeks, Barca's next move may depend on Zagreb's pretentions when it comes to the price.

Barca are well covered in attacking positions. Lionel Messi, Luis Suarez and Antoine Griezmann are the starting trio, with Ousmane Dembele, Ansu Fati and Carles Perez providing competition -- although Olmo's age and potential is a major plus.

In addition, Barca continue to monitor Paris Saint-Germain forward Neymar's situation with the view to a summer move, with sources telling ESPN last week the club still view the Brazilian as Messi's long-term heir.