"We believe these are by far the world's oldest bottles of beer," Rainer Juslin, a spokesman for the local government of Aaland, said in a statement.

The beer bottles were unearthed from a shipwreck believed to be about 200 years old -- as divers were recovering bottles of what is thought to be the world's oldest drinkable champagne, discovered in July.

The enviable haul, found intact on the seabed at a depth of 50 metres (yards), comes from an unidentified wreck which the Aaland authorities believe sank off the coast in the early 1800s.

"The constant temperature and light levels have provided optimal conditions for storage, and the pressure in the bottles has prevented any seawater from seeping in through the corks," Thursday's statement said.

The champagne bottles alone are estimated to be worth tens of thousands of euros.

Aaland, a semi-autonomous province of Finland, legally owns the contents of the wreck, but has yet to determine what to do with the champagne.