Catalonia will declare independence from Spain in a matter of days, the leader of the autonomous region has said.
In his first interview since Sunday's referendum, Carles Puigdemont told the BBC, his government would "act at the end of this week or the beginning of next".
Meanwhile, Spain's King Felipe VI said organisers of the vote put themselves "outside the law". He said the situation in Spain was "extremely serious", calling for unity.
Hundreds of thousands of people across Catalonia have been protesting over Spanish police violence during the vote, during which nearly 900 people were hurt, including 33 police officers.
In the BBC interview, Catalonia's President Puigdemont said if the Spanish government were to intervene and take control of Catalonia's government, it would be "an error which changes everything".
Puigdemont said there was currently no contact between the government in Madrid and his devolved administration.
He disagreed with the European Commission's statement on Monday that events in Catalonia were an internal issue for Spain. He was speaking shortly before the king's speech.
In his televised address to the nation, the king said the Catalan leaders who organised the referendum showed their "disrespect to the powers of the state".
"They have broken the democratic principles of the rule of law. Today, the Catalan society is fractured," the king said, warning that the poll could put at risk the economy of the wealthy north-eastern region and the whole of Spain.
But he stressed that Spain "will overcome difficult times".
The Spanish government has described the referendum as illegal.