Spain's Altamira cave, which contains some of the world's most important prehistoric paintings, will reopen to the public at the end of the year for the first time since 2002, the Spanish government said.

A panel of experts will determine how many people can enter the cave located some 30 kilometres west of the northern city of Santander without damaging the paintings, remarked Culture Minister Angeles Gonzalez-Sinde.

The cave, dubbed the Sistine Chapel of prehistoric art, is covered with paintings of bulls, bisons, boar and other animals etched in red, yellow and black that are estimated to be at least 14,000 years old.

Miguel Angel Revilla, head of the government of the northern region of Cantabria, said he hoped US President Barack Obama would be the first person to visit the cave when it reopens to the public.

"I have already written the invitation letter, and in English," he said.

The cave was first closed to the public in 1977 because the paintings were being damaged by the carbon dioxide from the breath of large numbers of visitors.

It was reopened in 1982 but with restrictions on the number of people who could visit it and remained open until September 2002.

Over the past eight years people have been able to visit a replica of the cave located nearby in the northern town of Santillana del Mar which has drawn 2.5 million visitors since it opened.

The cave, which was discovered in the late 19th century, was declared a World Heritage Site by Unesco in 1985.