Spain's deputy prime minister, Alfredo Perez Rubalcaba, has resigned to concentrate on running for prime minister in general elections the ruling Socialist Party is expected to lose.

Rubalcaba told reporters in Madrid Friday that Prime Minister Jose Luiz Rodriguez Zapatero has been informed of his desire to leave the government and do so immediately. Rubalcaba also said there was no legal obstacle to continuing in government even while preparing to contest the election.

Rubalcaba, who also serves as interior minister, is expected to be formally named as the Socialist candidate at a party meeting on Saturday.

The elections must be held by next March, although there is speculation that Mr. Zapatero, who is not seeking a third term, will call them early.

Mr. Zapatero's government is saddled with an economy struggling to overcome a recession and a jobless rate of 21.3 percent – the highest in the 17-nation euro zone. The prime minister has blamed the sour economy for his party's defeat at the hands of opposition conservatives in local elections this past May.

The conservative opposition Popular Party is expected to win the next general elections.