Fears mounted on Saturday over the rise of new cases and fatalities outside China from the coronavirus outbreak, as the World Health Organization warned of a shrinking window to stem the spread of the deadly disease.

The warning came as the first Europeans died from the new COVID-19 strain, which first emerged in December in central China but has now spread to over 25 countries and caused more than a dozen deaths outside the country.

A 78-year old Italian man died after testing positive for the virus just hours after 10 towns were locked down following a flurry of new cases. A second Italian victim, a woman from Lombardy, was confirmed to have died later on Saturday morning.

Iranian health authorities on Saturday reported a fifth death from the new virus that emerged in China, and said the fatality was from among 10 new confirmed cases of the virus in Iran.

It came as a number of cases were reported across the Middle East, including the first infections in Israel and Lebanon.

A second person died in South Korea, authorities reported Saturday, as the number of cases in the country spiked.

The Italian man from the Veneto region who had tested positive for the virus died in hospital, where he had recovered some 10 days earlier for an unrelated health issue, Italy's health minister said.