A major leak of a register that contained the details of nearly two million Chinese Communist Party members has occurred, exposing members worldwide.

Sharri Markson, Sky News host, said that the breach also lifts the lid on how the CCP operates under President and Chairman Xi Jinping.

“It is believed to be the first leak of its kind in the world,” the Sky News host said.

“What's amazing about this database is not just that it exposes people who are members of the communist party, and who are now living and working all over the world, from Australia to the US to the UK,” Ms Markson said.

“But it's amazing because it lifts the lid on how the party operates under President and Chairman Xi Jinping”.

The leak showed that CCP party branches are involved with some of the world's biggest companies and inside government agencies worldwide.

“Communist party branches have been set up inside western companies, allowing the infiltration of those companies by CCP members - who, if called on, are answerable directly to the communist party, to the Chairman, the president himself,” she said.

“Along with the personal identifying details of 1.95 million communist party members, mostly from Shanghai, there are also the details of 79,000 communist party branches, many of them inside companies”.

The leak is a significant security breach likely to embarrass Xi Jinping.

“It is also going to embarrass some global companies who appear to have no plan in place to protect their intellectual property from theft. From economic espionage,” she said.

The data was extracted from Shanghai servers by Chinese dissidents and whistleblowers back in April 2016.

“It was then leaked in mid-September to the newly-formed international bi-partisan group, the Inter-Parliamentary Alliance on China - and that group is made up of 150 legislators around the world.

“It was then provided to an international consortium of four media organisations, The Australian, The Sunday Mail in the UK, De Standaard in Belgium and a Swedish editor, to analyse over the past two months, and that's what we've done".

Ms Markson said it, “is worth noting that there's no suggestion that these members have committed espionage - but the concern is over whether Australia or these companies knew of the CCP members and if so have any steps been taken to protect their data and people”.