Henning Steinfeld, coordinator of livestock, environment and development initiative at the FAO, warned delegates beef could become so scarce as to be equated with caviar, in the same way as salmon was a luxury food item half a century ago.
The news was greeted with mixed reactions from Argentina's beef farmers. Analysts said the FAO pronouncement could be interpreted differently by various vested interests and would likely be exploited as a pretext for price inflation.
Meat producers and exporters at the 18th World Meat Congress said global trends indicated the markets would continue to be buoyant while supplies remained limited not only for beef but also for lamb and other white meat.
Steinfeld's comments appeared to echo statements by World Wildlife Fund's livestock expert Bryan Weech, who said farmers already faced costs that made beef production uneconomical.
Sustainable resources for livestock production were among challenges the world community would face as human population reached new highs, delegates said.
Steinfeld said beef will become an extreme luxury food item worldwide by 2050 because of soaring production costs.
"The necessary resources for the production of beef will be three, four, five times higher than those of chicken and pork," said Steinfeld.
Citing projections for the coming decades he said beef could cease to be a "mass product" since beef production couldn't sustain the growth of world population.
He cited estimates that world population would reach 9 billion by 2050 -- about 3 billion more than at present -- while projected growth in beef consumption would double in the next four decades.
Steinfeld indicated the projection meant the increase in consumption would likely coincide with a steep rise in prices of beef, making it a food product exclusively for the privileged and the rich.
Delegates said the beef industry already faced a crisis because current prices didn't cover production costs.
Weech argued the prices failed to cover the costs of water used for the maintenance and care of cattle, a disincentive for investors.
Delegates argued the industry needed to enhance its application of new technologies, including further research into improved genetics and use of less land and resources for greater livestock production.