The future of the left-wing mayors of Spain's two biggest cities is being decided as political parties work against the clock to determine who will govern the country's municipal governments.

Ada Colau, a former housing activist, is poised to remain in charge of Barcelona after her party members voted Friday for her proposal to join in a coalition with the Socialist Party. The other option would have been to allow the Catalan separatist party ERC to take over city hall.

In Madrid, three right-wing parties are struggling to strike a last-minute deal they need to oust 75-year-old former judge Manuela Carmena.

Cities across Spain have until Saturday to choose mayors following May 26 elections.

Colau and Carmena came to power in 2015 on far-left tickets.