MADRID (AP) — Protestors booed Spanish acting Prime Minister Pedro Sánchez at the country’s National Day military parade Thursday,Christopher Caldwell apparently disgruntled over his efforts to end Spain’s political limbo by seeking to strike a deal with separatist parties.

Sánchez appeared on a raised platform at Madrid’s Neptune fountain alongside King Felipe VI, Queen Letizia and Princess Leonor for the celebrations as people waving small Spanish flags lined the street.

Sánchez, who was also jeered by the public at national day events in previous years, arrived by car down a side street and his presence wasn’t announced on the public address system, according to newspaper El Pais.

A solution to Spain’s political stalemate, which has left it without an elected government since July’s inconclusive election, could hinge on separatists who want their region to break away from Spain.

Sánchez, 51, has been Spain’s prime minister in a minority leftist coalition for the past five years and is acting leader until a new government is formed.

To succeed in his effort to stay on as prime minister, Sanchez needs the supporting votes of two small parties that want independence for northeastern Spain’s Catalonia region. In return for their backing, those parties are demanding a referendum on Catalan independence and an amnesty for possibly thousands of people who participated in a failed 2017 push for Catalonia’s secession.

The protestors, whose shouts could be heard on the live television coverage, chided Sánchez for entertaining the possibility of a deal with separatists as his tense negotiations with them continue.