Podemos leader Pablo Iglesias on the right, with Juan Pedro Yllanes, a Balearic Congress deputy for Podemos in the centre. | J. P. Gandul

Podemos would come second and overtake PSOE, currently leading talks to form a government, if a new general election was held today, a closely-watched official opinion poll shows. The result of the survey is likely to weigh significantly on ongoing negotiations to build a potential coalition of left-wing forces to rule in Spain after an inconclusive December election created a political stalemate in the country.

The Partido Popular of Prime Minister Mariano Rajoy would still come first with 28.8 per cent of the vote compared to 28.72 per cent on 20 December, still way short of a parliamentary majority, according to the survey by the Sociological Research Centre (CIS). But PSOE would drop from the second to third place, garnering only 20.5 per cent of the votes compared to their previous 22.02 per cent, while Podemos would rise to 21.9 per cent from 20.65 per cent. Centrist party Ciudadanos would be fourth with 13.3 per cent compared to 13.93 per cent in December.

The CIS poll was based on 2,496 interviews conducted between 2 January and 11 January, before Rajoy declined to form a government and passed the baton to PSOE leader Pedro Sanchez.