Japan could lose $1.29 billion in tourism revenue in the January-March period due to international flight restrictions stemming from the new coronavirus outbreak, according to an estimate by a U.N. agency.

The International Civil Aviation Organization, or ICAO, attributed the estimate to reductions in Chinese air travelers, with the central China city of Wuhan being at the center of the outbreak.

Japan is followed by Thailand at $1.15 billion.

The Montreal-based ICAO reported some 70 airlines have cancelled all international flights to and from mainland China, and that a further 50 airlines have curtailed related air operations.

This has resulted in an 80 percent reduction in foreign airline capacity for travelers flying directly to or from China.

ICAO's preliminary forecasts indicate a reduction of 16.4 million to 19.6 million passengers compared to what airlines had projected for the first quarter of 2020.

Economic impacts of the new coronavirus, COVID-19, are expected to be greater than those caused by the 2003 epidemic of severe acute respiratory syndrome, or SARS, in light of the higher volume and greater global extent of the flight cancellations being observed.

The reduction of passengers equates to a loss of $4 billion to $5 billion in gross operating revenues for airlines worldwide.

The COVID-19 outbreak has killed more than 1,600 people and infected over 68,000 in mainland China alone.