But the move has been shrouded in secrecy and speculation.

Li hasn't been seen publicly for two months and China has given no comment on where he has been, why he's been sacked or who will replace him.

Coming just a few months after a very similar disappearance and removal, it fuels more speculation that there may be trouble at the very top of Xi Jinping's increasingly opaque government.

Question marks were first raised about where Li Shangfu was at the end of August when he skipped a meeting in Vietnam.

Since then, nothing has been seen or heard from him - fuelling intense speculation about his fate.

Li was one of China's most senior figures because while China's defence minister does not have command power, as they do in other countries, he was also one of China's five State Councillors - putting him at the very top echelons of China's Communist Party.

It is still very unclear what he has done wrong but there are some clues.

Just weeks before his disappearance, Xi called China's military top brass to a meeting in Beijing where he emphasised the importance of political loyalty and the "absolute leadership" of the party over the military.

Shortly afterwards, two heads of China's Rocket Force - an elite unit overseeing the nation's nuclear and ballistic missiles - were abruptly dismissed.

At roughly the same time, the military's Equipment Development Department announced a crackdown on corrupt procurement practices dating back to 2017 - precisely the time when Li Shangfu took over its leadership.

But while there is nothing new about corruption crackdowns claiming the careers of party officials, previously the most senior victims have been seen as Xi opponents.

Li, however, is thought to be a staunch loyalist.

Indeed, there could be another reason for his abrupt disappearance altogether.

But the affair has increased speculation about President Xi's authority and judgment.

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This is the second time in just three months a senior official and staunch loyalist has been purged.

Headlines were made around the world in July when the then foreign minister, Qin Gang, was finally dismissed after weeks of non-appearances.

It was rumoured he broke party discipline by having an extramarital affair, but this has never been officially confirmed.

Qin was thought to have been a particular favourite of Mr Xi and was promoted quickly above others who appeared to be more qualified.

The two instances are not flattering to the president as they come with the implicit suggestion that he's picking 'the wrong guys'.

Some commentators have even implied it points to a degree of chaos in the upper echelons of the party, a system now so centralised under the power of one person that it is not functioning smoothly.

Others refute this, arguing that it shows just how secure in his power Xi is, that he is able to take such decisions without concern for his image or the repercussions.

But be in no doubt the image does matter, certainly as far as the international community is concerned.

Indeed, at a time when China is desperately trying to welcome foreign investment to boost its faltering economy, such a lack of transparency or explanation doesn't do much to sell China as a productive place to do business.

Inadvertently, Li Shangfu being gone might actually help to improve China-US relations.

He was subject to US sanctions and China has been refusing high-level military-to-military meetings while those sanctions remained. That impediment has now been removed.

But this latest episode has plenty more negative implications and arguably says a lot about China's government under Xi Jinping - a system which is increasingly opaque, inward-looking, and unwilling to explain its reasoning.

Over time that is not necessarily a reputation that will serve it.