MADRID — Spain’s conservative government appeared doomed Thursday to lose a no-confidence vote in Parliament, with the center-left Socialist party poised to take power.
A Basque nationalist party’s announcement that it would vote in favor of the motion spelled the almost certain end of Prime Minister Mariano Rajoy’s mandate and foretold the stunning collapse of his minority government in a parliamentary vote Friday, when it will be short of support to survive.
Officials of Rajoy’s Popular Party dismissed speculation he might resign ahead of the vote.
‘‘The PP has faced up to all the problems that have come its way,’’ party secretary-general and Defense Minister Maria Dolores de Cospedal said, adding Rajoy will be present for the vote that’s expected to oust him. The impending downfall of his government after nearly eight years came days after the Popular Party’s reputation was badly damaged by a court verdict that identified it as a beneficiary of a large kickbacks-for-contracts scheme.
That development injected a new element of tension into European Union politics and global financial markets, already unsettled by Italy’s struggles since a March 4 election to install a government.
Under a Spanish law that prevents a power vacuum, Socialist leader Pedro Sanchez, who tabled the no-confidence motion, would immediately become the new leader of the 19-country eurozone’s number four economy and a prominent EU leader.
Unlike Italy’s potential new leaders, Sanchez hasn’t expressed skepticism about the EU or the continent’s single currency, both of which are popular in Spain.
In the no-confidence debate, Sanchez, 46, called on Rajoy to step down over the kickbacks scandal. ‘‘Resign and everything will end,’’ Sanchez told the prime minister. ‘‘Mr. Rajoy, your time is up.’’
Rajoy responded by accusing Sanchez of a power grab.
‘‘Everybody knows that Pedro Sanchez is never going to win the elections and this is the reason for his motion, his urgency,’’ Rajoy told lawmakers, reminding them the Socialists lost two general elections under Sanchez’s leadership and warning that a Socialist government would endanger the country’s financial stability.
Sanchez promised to abide by a national budget recently negotiated by Rajoy. It includes substantial benefits for Basque nationalists, whose promised votes in the no-confidence debate opened the door for Sanchez to oust Rajoy.
Sanchez also vowed to open talks with separatists in the Catalan regional government over their demands for independence. That issue has dogged Spain for eight months.
Rajoy has been in power since 2011, steering Spain out of its worst economic crisis in decades during the eurozone debt crisis and achieving some of the strongest economic growth in Europe. Last year, gross domestic product growth reached 3.1 percent.
But Rajoy faced down opponents who complained that the recovery came at the expense of austerity measures, just as he successfully stood up to Catalan secessionists.
A strong economy wasn’t enough to keep Rajoy in power; he was undone by the corruption scandal. Last week, National Court judges delivered hefty prison sentences to 29 business people and Popular Party members, including some elected officials, for fraud, money laundering and tax evasion, among other crimes. Judges questioned the prime minister’s credibility when he said he was unaware of the fraud.
