Singapore's Changi Airport, voted as the world's best for the eighth consecutive year in 2020, on Monday warned of a "daunting period" ahead due to the impact of the ongoing Covid-19 pandemic.

In the wake of the global health crisis, the airport suspended operations in two terminals as flights have dropped to the lowest levels in its history, and also halted the construction of a fifth one for at least two years, the BBC reported.

In its annual report, the airport said: "The battle with Covid-19 has only just begun. The future does appear daunting with the situation showing no signs of abatement."

It said that the recovery was "highly dependent on how countries around the world manage border controls, the relaxation of air travel requirements and the development of viable medical treatments for the virus".

Singapore barred the entry and transit of short-term visitors on March 23, which resulted in profits to plunged 36 per cent to S$435 million.