CATALAN political prisoners who are on trial over the 2017 independence referendum and who are standing in forthcoming elections will not be freed to take part in campaign events.

Former vice-president Oriol Junqueras, who leads Esquerra Republicana – the Republican Left of Catalonia (ERC) – is the highest-profile candidate who is standing for Congress in Spain’s snap election on April 28, called by Prime inister Pedro Sanchez.

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Jordi Turull, Josep Rull and Jordi Sànchez are all running under the Together for Catalonia (JxCat) banner, also for places in Congress, while Raül Romeva is ERC's first candidate for the Senate.

Judges at their trial yesterday dismissed a petition calling for their release to allow them to take part in election campaigning, claiming that their “preventative detention” was “proportionate” and did not violate their rights.

However, Spain’s legal system will allow them to leave prison to formally take office if they are elected.