BEIJING — In his first speech to the Chinese Communist Party’s elite Politburo, Xi Jinping, the new party chief, denounced the prevalence of corruption and said officials must guard against its spread or it would “doom the party and the state.”

Xi made the blunt remarks Saturday at a meeting of the 25-person Politburo, which announced a turnover of 15 members last week during the change in leadership at the close of the 18th Party Congress, the state news media reported Monday.

Xi’s admonitions were consistent with warnings that Chinese leaders have delivered in recent years and echoed points he made in his inaugural speech last Thursday. Xi appears to want to take a populist tack inshaping his image and to push an anti-corruption drive as one of the first visible acts in his new post. Corruption is one of the issues of greatest concern to ordinary Chinese.

“In recent years, the longpent-up problems in some countries have led to the venting of public outrage, to social turmoil and to the fall of governments, and corruptionand graft have been an important reason,” Xi said, according to a version of the speech posted online.

“A mass of facts tells us that if corruption becomesincreasingly serious, it will inevitably doom the party and the state. We must be vigilant. In recent years, there have been cases of grave violations of disciplinary rules and laws within the party that have been extremely malign in nature and utterly destructive politically, shocking people to the core.”

Xi used a Chinese aphorism - “worms come only after matter decays” - to stress his point. The phrase is often attributed to Su Shi, a scholar of the Northern Song Dynasty, and it was also cited on several recent occasions by BoXilai, the ousted party chief of Chongqing who was felled last spring by a murder scandal and is expected to stand trial soon on criminal charges related toabuse of power. When Bo used the phrase in speeches, it was also in the context of denouncing corruption and enhancing his populist image. Ironically,Xi’s allusion to recent “grave violations” of party discipline appeared to refer in part to Bo.

Both Xi and Bo are sons of powerful Communist leaders, and Bo, a former Politburo member, was seen as a rival to Xi.

Xi also took the occasion Saturday to underscore the need to remain true to the party’s founding ideology, and warned that some officials appeared to be heading down a wayward path in this area, too.

“Faith in Marxism and abelief in socialism and communism is the political soul of a Communist and the spiritual pillar that allows a Communist to withstand any test,” Xi said. “To put it more vividly, ideals and convictions are the spiritual calcium of Communists, and if these ideals and convictions are missing or irresolute, then there is a lack of spiritual calcium that leads to soft bones.”

“In present-day life, all kinds of problems have arisen with some party members and officials, and in the end these amount to a loss of faith and spirit,” he added.

Pu Zhiqiang, a rights lawyer, said in an interview on Monday that Xi’s speech signaled that the party would pay more attention to corruption, but he also pointed out that “every generation of leaders hasmentioned that. No one would neglect paying attention to the problem of corruption. It’s common sense. The crux of the matter is how to implement anti-corruption measures.” Information for this article was contributed by Patrick Zuo of The New York Times.

Front Section, Pages 7 on 11/20/2012