A donation by Swiss drug maker Roche, of enough of its Tamiflu antiviral drug to treat 3 million people against birdflu, could slow the spread of the outbreak among humans, especially in countries too poor to afford their own stockpile.
The donation to the World Health Organization (WHO) will help establish a first line of defense against a feared global bird flu pandemic.
The pharmaceutical giant announced its intention on Wednesday.
WHO Director-General Lee Jong-wook says that if a flu pandemic were to emerge, the drugs could be flown quickly to the center of a potential pandemic.
He warns that if a pandemic did happen and there are no preparations, there would be millions and millions of deaths.
Fears of a global outbreak have re-emerged since the avian virus spread recently from Asia into Siberia in eastern Russia and Kazakhstan.
The WHO and other experts have been repeatedly urging governments to buy in antiviral drugs like Tamiflu and Relenza.
Health officials in another Siberian region, the Altai Republic, said the virus had been found in a wild duck there, but the agriculture ministry in Moscow has said its spread had been curbed.
Although an Altai government statement said samples taken from the bird shot on August 13 indicated the presence of bird flu virus "of the fifth type", it did not say whether the strain was the H5N1 which has killed at least 50 people in Asia since 2003 and forced the slaughter of millions of poultry which carry it.
The WHO says it is monitoring the outbreaks, as all have the potential to trigger a global pandemic if the virus mutates and becomes easily transmittable between humans.
In the last major flu pandemic in the late 1960s, 4 million people died and health authorities say another is long overdue.
While drug companies are currently working on a vaccine against H5N1, the WHO says that in the meantime, antiviral drugs are the best option and recommends governments stockpile neuraminidase inhibitors, the class of drugs to which Tamiflu belongs.
It has been reported that Margaret Chan, WHO director for pandemic influenza preparedness, is in talks with another firm about another type of inhibitor.
Although she declined to give details, the only other drug on the market is Relenza, made by Britain's GlaxoSmithKline.
GlaxoSmithKline is currently caught up in a legal battle with Biota, Relenza's creator, over Glaxo's failure to support Relenza on the global market.
Swiss-based Roche says it will set aside 3 million packs of 10 Tamiflu pills, the dose is 2 a day for 5 days.
According to company executive David Reddy, the stockpile, which comes in the form of capsules, would be good for 5 years.
Reddy says the stockpile of Tamiflu will not be directed toward any specific country, but rather give rapid access to the drug for use at the site of an outbreak of influenza.
Roche has already received orders from around 30 countries, including Britain, France and Germany, for enough of the drug to cover between 20 and 40 percent of their populations.
However Lee warns that the drugs, although they could buy time, were not in themselves enough and countries must step up surveillance and develop their own plans for an outbreak.
According to the WHO, only 40 countries have so far heeded its call for national contingency plans for a flu pandemic.