MADRID (AP) — The head of Spain’s main opposition Socialist party will step down following dismal results in the European Parliament election.

Alfredo Perez Rubalcaba said Monday he took full responsibility for the “unreservedly bad” results.

The Socialists won 14 seats, down from 23 in 2009.

The ruling conservative Popular party won the most seats but it too suffered a drop, from 24 to 16. It was both parties’ worst result ever.

Rubalcaba said the Socialists will hold a party congress on July 19-20 to name a new leader.

A member of three Socialist governments, Rubalcaba, 62, declined to say what his own plans were.

Many Spaniards blame the Socialists for allowing Spain to slide into economic crisis but are also angry with the Popular Party for imposing tax hikes and cuts.

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