REPUBLIKA.CO.ID, MADRID/BARCELONA -- Ousted Catalan leader Carles Puigdemont called on Saturday for a united political front in the Dec. 21 election to continue the drive for independence from Spain and to protest against the imprisonment of former members of the regional government.

Puigdemont, who went to Belgium after his government was fired following a unilateral declaration of independence, said on Friday he was considering standing in the election from Brussels.

In Spain's gravest political crisis since the return of democracy in the late 1970s, Prime Minister Mariano Rajoy called the snap election after taking control of Catalonia a week ago.

Political parties that wish to run on a common platform have until Tuesday to register any potential coalition and until Nov. 18 to put forward their candidates.