Advance of far-right parties is the ‘biggest concern’ for Western democracies, Spain’s Prime Minister says

The rise of far-right political groups is the "biggest concern" for Western democracies, Spanish Prime Minister Pedro Sánchez told CNBC.

"I think that not only the [political] fragmentation, but the advance of the far-right, it is something … I would say [it is] the biggest concern for Western democracies," Sanchez said at the World Economic Forum in Davos, Switzerland.

His comments come in a year set to bring voters to the polls in several countries worldwide, which will include European Parliament elections in June.

Support for far-right groups has bolstered in some European nations. In France, Marine Le Pen's National Rally party has grown in popularity in the polls, while Geert Wilders' Freedom Party recorded a decisive victory in Netherlands' general elections in November.

Addressing a trend of political fragmentation, Sánchez noted how some right-wing parties in the European Union have had to form coalition agreements with far-right parties. In Spain, the conservative People's Party forged an alliance with far-right Vox during Alberto Nunez Feijoo's failed bid to gain parliamentary approval for his investiture as prime minister last year.

Alliances are "the major decision that the popular party at the European level must take," Sanchez said.

The Spanish prime minister said it is "important that we stick to the previous agreement that we reached – the three biggest families, the largest families of the European Union politically which is the social democracy, the liberals and the popular party."

He said that having more progressive or center seats than far-right seats in the European Parliament would be "easier for all of us, the Commission, the Council and of course, the European Parliament."

Sánchez secured another term