BEIJING (Reuters) - China’s military must resist the “corrosion” of corruption and ensure the fight against graft is deepened, President Xi Jinping told senior officers, state media said on Sunday, offering a renewed warning against a deep-seated problem.

FILE PHOTO: Chinese President Xi Jinping inspects troops at the People's Liberation Army (PLA) Hong Kong Garrison as part of events marking the 20th anniversary of the city's handover from British to Chinese rule, June 30, 2017. REUTERS/Damir Sagolj

China’s military, the world’s largest and currently undergoing an ambitious modernization program, has been an important focus of Xi’s campaign against corruption since he took power six years ago.

Xi has repeatedly warned about the threat of corruption to the country and the party, and has vowed not to let up in the fight against it.

Dozens of officers have been investigated and jailed, including Xu Caihou and Guo Boxiong, both former vice chairmen of the Central Military Commission, which Xi heads and is in overall charge of the People’s Liberation Army.

Guo was jailed for life in 2016. Xu died of cancer in 2015 before he could face trial.

Speaking at a three day-meeting of the Central Military Commission, which ended on Sunday, Xi said the fight against graft must remain “always on the road” and be deepened, the official Xinhua news agency reported.

“Go in hot pursuit of and strike hard against hedonism and extravagance,” Xinhua cited Xi as saying. “The anti-corruption fight must be unswervingly grasped, and will not change direction or form.”

There must be no no-go areas and a zero tolerance attitude maintained, with a full and comprehensive supervision system put in place to tackle the problem, he added.

China’s military must ensure they and their families are upright and clean, and that they can “resist the corrosion of unhealthy tendencies”, Xi said.

He also said efforts were needed to strengthen the leadership of the ruling Communist Party over the military “to ensure a solid political guarantee for the building of a strong military.”

Serving and retired officers have said graft in the armed forces is so pervasive it could undermine China’s ability to wage war.

The anti-graft drive comes as Xi steps up efforts to modernize forces that are projecting power across the disputed waters of the East and South China Seas and deep into the Pacific Ocean, though China has not fought a war in decades.