Catalonia’s leader has put independence from Spain on hold to allow for talks with Madrid.
In a highly anticipated speech, Carles Puigdemont told the regional parliament in Barcelona he accepted the “mandate of the people” for a split.
But he asked the Catalan parliament to “suspend the effects of the independence declaration to initiate dialogue in the coming weeks”.
Mr Puigdemont criticised the Spanish government’s response to the region’s disputed independence referendum, but said Catalans have nothing against Spain or Spaniards.
He said: “We’re not criminals, we’re not mad. We’re normal people who want to vote.”
Although Mr Puigdemont stopped short of seeking the explicit support of the chamber for the declaration in a formal vote, his gambit plunges Spain into the unknown.
Voters in Catalonia backed independence in a referendum last weekend, a poll that was declared illegal by Madrid even before it took place.
Although 92% of those who voted backed secession, only 43% of Catalans cast a ballot.
The Spanish government was the subject of international condemnation for its response to the vote, which saw rubber bullets fired and batons used on crowds.
Responding to Mr Puigdemont’s speech, a Spanish government official said Madrid did not accept Catalonia’s “implicit” independence declaration, while the opposition leader in Catalonia’s parliament accused Mr Puigdemont of a “coup”.
Madrid has previously promised action to “restore law and democracy” if Catalonia presses ahead with independence.
Tuesday’s proclamation makes a negotiated settlement more difficult, as Spanish Prime Minister Mariano Rajoy has said he would not talk to Catalan leaders until they drop plans for secession.
One of the options open to Mr Rajoy is the unprecedented step of dissolving the region’s parliament and triggering new elections, a prospect that has been referred to as the “nuclear option”.
Madrid could also ask the courts to strike down a declaration of independence as unconstitutional.
European leaders have also come out against an independence declaration, amid concerns about Spain’s biggest constitutional crisis since its transition to democracy in the wake of the death of military dictator Francisco Franco in 1975.