Portugal has become the first European Union country to ratify the bloc's budget discipline treaty, the co-called Fiscal Compact.
Parliament approved the accord on April 13 by 204 votes to 24, with the governing conservative coalition and the main opposition socialists backing the treaty.
Three far-left parties voted against the pact.
The Fiscal Compact tightens control over public finances and envisages penalties for countries running up deficits.
It was signed by 25 out of the 27 EU nations at a summit in March.
In order to come into force, it must be ratified by at least 12 of the signatories.
Portugal is one of the 17 eurozone countries hardest-hit by the current crisis.
It became the third eurozone country after Greece and Ireland to be bailed out by the EU and the International Monetary Fund.
Based on reporting by dpa and AFP