Spain's parliament has agreed to study a proposal that seeks greater autonomy for the northeastern region of Catalonia.
The early morning vote, with 197 votes in favour and 146 against, followed more than 10 hours of intense debate. Only the conservative Popular Party, led by Mariano Rajoy, voted against the proposal, arguing that it put Spain on a path to dissolution.
Socialist Prime Minister Jose Luis Rodriguez Zapatero said he was willing to negotiate the proposals, adding that the wealthy region has a constitutional right to seek more self-rule.
But he challenged the reform package's description of Catalonia as "a nation", which many conservatives have dismissed as separatist and unconstitutional.
Mr Zapatero said Catalonia, whose capital is Barcelona, "has a national identity and this is compatible with the constitution".
The Barcelona daily La Vanguardiadescribed the session as "a great day for Catalonia and for Spain," But conservative newspapers felt Mr Rajoy had triumphed, saying his speech revealed Mr Zapatero's weaknesses.
The vote is only the first hurdle for the autonomy proposal. It must now be taken up by a committee for possible amendments, and a definitive vote is likely to be several months away.