The Spanish liberal party Ciudadanos is increasingly polarised over the question of cooperation with the far-right Vox party.

Ciudadanos, or ‘Citiznes’ in Spanish, are members of the liberal Renew Europe group that emerged from the merger of Alliance of Liberals and Democrats for Europe (ALDE) and the French La Republique en Marche (REN) of French President Emmanuel Macron. The leader of the Ciudadanos group in Brussels, Luis Garicano, wants his party to support the formation of a government led by incumbent Socialist Prime Minister Pedro Sánchez.

In the countdown to the April general elections, Ciudadanos was frequently polling ahead of the conservative Popular Party and became the leading force of the centre-right. But the advent of Vox has divided the liberals more than the Popular Party. Three high-ranking members of Ciudadanos recently resigned including Toni Roldán, the party spokesman for economic affairs, Javier Nart, a member of the European Parliament; and Juan Vázquez, the party chief in the northern region of Asturias.

The three resignations come as the leadership of Ciudadanos refuses to discuss the formation of a coalition government with the incumbent Socialist (PSOE) but is instead allowing cooperation at a local level with Vox, a party that is openly nostalgic for the days of Fascist dictator Francisco Franco.

Roldán argues that the party’s shift to the right betrays the party’s commitment to battle against nationalism. The origins of Ciudadanos is Catalonia and it is now the leading party of the centre-right in the autonomous region that is torn between unionism and a largely left-wing secessionist movement. “How can we build a liberal project in Spain if we are unable to confront the far right,” Roldán asked in a televised statement.

Roldán is not alone. Four out of 24 members of the Ciudadanos executive committee voted in favour of a motion to form a government led by Sánchez. Ciudadanos have 57 seats in parliament, which together with the Socialists’ 123 seats would provide a stable two-party government in Spain’s 351-seat lower house. While Podemos have pledged their support, their 42 seats and their fractious structure means that Sanchez would lead an inherently unstable minority government.