China has revised the death toll in coronavirus ground-zero Wuhan, revealing that nearly 4,000 people have died from the illness in the area.

In a social media post, the city government added 1,290 deaths to the tally in Wuhan, bringing the toll to 3,869.

Officials said many fatal cases were 'mistakenly reported' or missed entirely in an admission that comes amid growing global doubts about Chinese transparency.

The global pandemic originally emerged in Wuhan. The city went on to suffer the vast majority of China's fatalities from Covid-19, the disease caused by the virus.

Medical staff in Wuhan are seen removing the body of a person suspected to have the coronavirus

The change also pushes the nationwide death toll up by nearly 39 percent to 4,632, based on official national data released earlier on Friday.

Numbers of total cases in the city of 11 million were also raised by 325 to 50,333, accounting for about two-thirds of China's total 82,367 announced cases.

China has come under increasing pressure over the coronavirus pandemic from Western powers led by the United States, which has raised doubts about Chinese transparency and is probing whether the virus actually originated in a Wuhan laboratory.

This photo taken on February 28, 2020 shows medical staff transferring a patient infected by the COVID-19 coronavirus at the Red Cross hospital in Wuhan in China's central Hubei province

China has said the virus emerged from a Wuhan food market whose merchandise reportedly included exotic wild animals sold for human consumption.

Wuhan's epidemic prevention and control headquarters cited several reasons for the missed cases, including the fact that the city's medical staff were overwhelmed in the early days as infections climbed, leading to 'late reporting, omissions or mis-reporting'.

It also cited insufficient testing and treatment facilities, and said some patients died at home and thus their deaths were not properly reported.