The Red Cross has put out an urgent call for blood donors with stocks of Australia's two most common blood types running critically low.
Red Cross Lifeblood is appealing for 16,000 additional people to give blood or plasma during the next two weeks.
All blood and plasma types are needed, but in particular, supplies of O+ and A+ blood have now dropped to two days' supply.
Lifeblood Executive Director Cath Stone said fewer donors had been making appointments recently and around the nation, 1200 donors each day were cancelling or not turning up for their donations.
Ms Stone said 31,000 donations were needed every week across Australia to help patients in times of trauma, major surgery, cancer treatment, pregnancy and a host of other situations.
"This recent trend of decreasing appointments and increasing cancellations is concerning."
Around 71 per cent of the Australian population has an O+ or A+ blood type.
