Spain's foreign minister has repeated his government's position that the sacked Catalan leader could run in new elections in December, but stressed that meant only if he was not in jail.

Alfonso Dastis spoke as a huge rally for Spanish unity was held in Catalonia's largest city, Barcelona.

Carles Puigdemont was removed from office after Madrid stripped Catalonia of autonomy for declaring independence.

Spain's central government has now taken control of Catalan institutions.

Spain's chief prosecutor is preparing to file criminal charges against Mr Puigdemont and other Catalan officials for breaching Spanish law.