MADRID (Reuters) - Spain's former Socialist leader Pedro Sanchez launched a bid to regain leadership of the party on Saturday, four months after he was toppled for refusing to end a political stalemate that gripped the country for almost a year.


The Socialist party, which came second in an election last June behind Prime Minister Mariano Rajoy's conservative People's Party, will hold primaries in May. It has been under interim management since Sanchez was forced to stand down in October.


Sanchez resigned when a majority of the party's assembly voted to abstain in a confidence vote to grant Rajoy a second term, something Sanchez had opposed steadfastly.


Sanchez told supporters in the southern city of Seville, which he called the "heart of Spanish socialism," that he still believed the party had been wrong to abstain and if elected he would make a stand against the PP's economic policies.


"It is the time to commit, to give our best. I am not the same as I was three years ago, I have more experience and I am more eager than ever," he said.


In the leadership race, Sanchez, 44, will run against former parliament speaker Patxi Lopez, one of his chief allies during his time as leader. The powerful head of the Andalusian region, Susana Diaz, is also expected to stand, although she has not announced her candidacy yet.

As a result of the Socialists' rifts over the abstention vote, the party has sunk in the polls and would be in third place behind anti-austerity Podemos if another election were held, recent opinion polls have shown.

(Reporting by Angus Berwick and Rodrigo de Miguel; Editing by Helen Popper)