The Spanish nationalist right appears to have benefited from its uncompromising stance against Catalan separatism with the latest polls projecting it would come close to doubling its number of seats in next month’s election.

It has also gained support from its opposition to the acting Socialist government’s decision to exhume the body of General Franco, the fascist dictator, from a monumental civil war mausoleum and bury him in a cemetery.

Vox, which became the first ultra-conservative party to win representation since the restoration of democracy in 1978 when it claimed 24 seats in an inconclusive ballot in April, is now on course to win 41 seats, almost doubling its tally of MPs in the 350-seat lower house.

The centre-right Popular Party (PP), which suffered