Residents of a suburban New York City county that was one of the earliest US hot spots for the coronavirus have sued the World Health Organisation, accusing it of gross negligence in covering up and responding to the Covid-19 pandemic.

In a proposed class action, three residents of Westchester County accused the WHO of failing to timely declare a pandemic, monitor China's response to the original outbreak, provide treatment guidelines, advise members on how to respond including through travel restrictions, and coordinate a global response.

They also accused the WHO of conspiring with China's government, which was not named as a defendant, to cover up Covid-19's severity.