China has reshuffled its military top brass in a move analysts said Monday was probably aimed at ensuring President Hu Jintao remains commander-in-chief of the military after a 10-yearly leadership change.

At a top Communist Party meeting Sunday, Hu oversaw the promotion of Generals Fan Changlong and Xu Qiliang as vice chairmen of the powerful 12-member Central Military Commission (CMC), Xinhua news agency said.

Hu, the CMC chairman, is set to step down as head of the ruling party at a congress starting this week and will retire as national president in March as part of the leadership change.

But Willy Lam, a China politics expert at the Chinese University of Hong Kong, said: "Hu Jintao would want to serve another five years (as CMC chief), particularly given the fact that he has to watch over his political proteges... and protect his political legacy."

"As long as he is the CMC chief, he will still be the power behind the throne."

According to Lu Siqing, head of the Hong Kong-based Information Centre for Human Rights and Democracy, which seeks to advance political reform in China, both promoted generals have close ties to Hu.

Xu is the first air force general to become a vice chairman of the committee, and his ascension also reflects the importance China places on quickly developing its air capability.

China's 2.3-million-strong military forces -- the world's biggest -- include nuclear-tipped ballistic missiles and a recently commissioned second-hand aircraft carrier purchased from Ukraine.

The two incoming CMC vice chairmen will be tasked with pushing forward the modernisation of the military and overseeing the increasingly powerful arsenal.

Unlike most modern states the military is directly run by the ruling communist party, not by the government, an arrangement that stems from the revolution that brought the party to power in 1949.

The late revolutionary leader Mao Zedong -- who said that "power comes from the barrel of the gun" -- used the People's Liberation Army not only to advance revolution, but also to protect the party's political power, Lam said.

Hu took over control of the party from Jiang Zemin in 2002 but, as part of China's opaque and secretive political process, only succeeded him as CMC chairman in 2004.

There was also a possibility that Hu would only retain the CMC chairmanship for an extra two years, Lam said, long enough to let him influence the naming of the future heir to Xi Jinping, his own successor as party head and president.

He could also protect his protege Li Keqiang, who is set to take the place of outgoing Prime Minister Wen Jiabao, and seek to place other key allies in top posts at the 19th Party Congress in 2017, Lam added.

Xi was effectively chosen as China's next core leader in 2007 in a selection process heavily influenced by Jiang, who had already stepped down.

In a statement, Lu said: "Hu Jintao will seek to continue on as chairman of the Central Military Commission for another five years until 2017.

"This is due to worries over Xi Jinping among a lot of people in the higher levels of the military."

Xi was named a CMC vice chairman in 2010 in a rocky approval process that reportedly took more than a year to complete.

"If Hu Jintao retains his seat for another year or so, this certainly maintains the previous political practice," Kenneth Jarrett, a China-based director for the APCO Worldwide consultancy, told reporters.

"But I would say it's not good for China in the sense that you have a divided leadership, where you have Hu Jintao who will have the allegiance of the military at the very top even though he has given up all of his other positions."