In a statement issued last night, the government said it received a notice from Shanghai-based Fosun Pharma, which said the vaccines will fail to arrive in time as the export process has yet to be completed in Germany.

But authorities said the delay had nothing to do with European Union restrictions on Covid-19 vaccine exports and stressed the one million doses of the BioNTech vaccine will be delivered in two batches "as soon as possible."

The statement came 11 hours after Secretary for the Civil Service Patrick Nip Tak-kuen said yesterday morning that several hundred thousand doses of the vaccine were set to arrive in Hong Kong today.

Nip, responsible for the inoculation program, said the first batch will be going to the Hospital Authority.

According to the authorities, 24 community vaccination centers have been reserved for the BioNTech vaccinations.

Nip also said bookings for the third week of Sinovac inoculations will open within a few days, while priority groups could also start receiving jabs at 1,500 private clinics from next week without booking in advance.

Private doctors "will let the Department of Health know how many doses of Sinovac vaccine they would like to obtain," Nip said.

The authorities will upload details online, including doctors' information and locations of the private clinics.

A total of 532 people received a mainland-made Sinovac jab at the Central Library on Tuesday, including 214 people from different priority groups and 318 people who were wrongly allowed to sign up for the vaccine due to a system glitch.

In all, more than 70,000 people signed up for the Sinovac jabs, Nip added, reassuring residents that supply was sufficient.

Nip said the community vaccination center can serve up to 2,500 vaccine seekers a day, but the number can go higher once staff members become more familiar with the procedure.

He added that government departments are working to improve the online registration system.

Meanwhile, elderly residents at 10 care homes in a pilot vaccination program will get to choose between BioNTech and Sinovac jabs.

The Social Welfare Department has sent letters to the 10 care homes, asking them what type of vaccine the residents would like to receive.

Residents and staff who choose the Sinovac vaccine can start receiving their jabs in mid-March while those who opt for BioNTech will have to wait until late March.