The Barcelona football team have lent their support to a proposed independence referendum for Spain's Catalan region.

The President of Catalonia, Carles Puigdemont, wants to hold an independence referendum later this year.

A brief statement released by the reigning Spanish champions said they "agreed with the National Pact for the Referendum, the campaign to gather support from institutions, organisations, those in elected office and individuals inside and outside Catalonia."

Catalonia is currently governed by the Junts Pel Si (Together for Yes) coalition that backs breaking away from the rest of Spain.

Puigdemont has promised to hold a referendum in September, regardless of whether Spain's Prime Minister Mariano Rajoy agrees.

Rajoy has already stated several times that he will not permit a referendum, saying the Spanish constitution does not allow it.

A non-binding vote was held by the Catalan government in 2014, with more than 80 per cent voting in favour of independence.

Former Catalan president Artur Mas was given a two-year ban from public office for organising the referendum, which was illegal.

Barcelona, currently top of La Liga and whose motto declares they are "more than a club", have always maintained close links with Catalanism.

In recent years the Catalan separatist flag, known as the "estelada", has become a frequent symbol among the club's fans.