The only exceptions have been major national or international events, such as the Shanghai World Expo and the Beijing Olympic Games, when outside donations were transported to host cities to ensure the local supply's security.

Many locations have faced donor and supply shortages since October, including much of North China, Yunnan, Shandong, Jilin and Hubei provinces, earlier reports said.

"The situation may become direr", as students return home for winter break and migrant workers also travel back for the traditional Chinese New Year, Beijing Red Cross Blood Center head Liu Jiang said.

Deng urged the public, particularly permanent residents, to roll up their sleeves to form a stable donor pool to meet blood banks' rising demand.

"That could eliminate seasonal blood shortages and improve blood safety," he said.

Health Minister Chen Zhu had called on public servants to fulfill their responsibilities through unpaid voluntary blood donations in late October.

Certain employees at government departments and related agencies donate blood in return for money and days off.

Deng also pledged greater transparency in managing blood collection and supply, although some people suspect corruption in the system.

More than 60 countries have reached the point where all donations are non-remunerated and voluntary, World Health Organization figures show.