International collectors are renowned for snapping up wines that have matured over several decades - but what's the price of a liquor that is 2,000 years old?

Archaeologists are toasting the discovery of a vintage wine in the tomb of a nobleman in Xi'an, capital city of Northwest China's Shaanxi Province.

More than 25 kilograms of the wine were contained in a bronze zhong that was rescued from the path of bulldozers clearing the way for the city's latest high-rise.

The wine dates from the early Western Han dynasty (206 BC-AD 24) and its raw lacquer seal has kept it perfectly air-tight over the centuries.

It has already passed the taste test of wine experts, who described it as having a delicious aroma and light flavour with a low degree of alcohol.

But drinkers used to their favourite white rice wines should be warned - this particular vintage is green.

Qiu Xinyin, a wine expert at Xi'an Liquor Factory, said some ancient wines were fermented to be this colour.

A more likely explanation is that wines turn green over a long period of time, and this one has oxidized with the bronze container.

Sun Fuxi, director of Xi'an Archaeology Research Institute, said this was the largest amount of liquor ever discovered that dates from the Western Han period.