German airline giant Lufthansa said Friday it would prolong its suspension of flights to the Chinese mainland until March 28 over the novel coronavirus COVID-19.

"The Lufthansa Group has now decided to cancel the flights of Lufthansa, Swiss and Austrian Airlines from/to Beijing and Shanghai until the end of the winter timetable on 28 March" rather than 29 February, the group said in a statement.

Lufthansa flights to Nanjing, Shenyang and Qingdao were already cancelled until the same date.

Meanwhile the group will respond to reduced demand for Hong Kong flights by cancelling some flights by flagship carrier Lufthansa and using smaller planes on Swiss connections.

Passengers whose has been cancelled can change their booking at no charge or receive a full refund, Lufthansa said.

On Thursday, UN body the International Civil Aviation Organization (ICAO) estimated almost 20 million fewer passengers would travel to and from China in the first quarter compared with expectations, costing the up to $5 billion in revenue worldwide.