Relaxed security measures at mainland airports, announced on Wednesday and due to come into effect today, were postponed yesterday at the last minute.
The restrictions would not be eased for now because of 'practicalities and work requirements', the Civil Aviation Administration of China (CAAC) said in a statement on its website announcing the delay.
The statement offered no further explanation.
It said only that all passengers should abide by existing restrictions.
The CAAC had planned to allow passengers boarding domestic flights to take cigarette lighters, matches and up to 1 litre of liquids in 100ml containers on board planes.
They would also have been allowed to take into aircraft cabins liquid medicines and milk for babies if certified by a hospital and subject to security checks. But for now, they will have to follow existing rules requiring them to use milk supplied by airlines and to hand liquid medicines to flight crew.