Top British archaeologists are urging the government to rethink a law requiring human remains be reburied, warning it risks undermining years of research into the island's ancient peoples and study of their DNA.

The row stems from the reinterpretation of a law introduced in 2008 by the Ministry of Justice. The rule states human bones discovered in England and Wales since that time, regardless of their age, must be re-interred after two years.

In a letter to Justice Secretary Kenneth Clarke, 40 academics complained experts would have too little time to study the remains and that reburial would result in the needless destruction of immensely valuable material.

Important sites that will be affected include Stonehenge and a Viking mass burial pit near Weymouth on the south coast.

Many archaeologists believe secrets about ancient tribes and early humans in Britain could be lost to science forever if the rule is applied. Thousands of sites could be affected in the future, they say.

"Britain risks losing its leading role in archaeology, a decline that will be observed by a mystified international scientific community," the letter said.

"The current license conditions are impeding scientific research, preventing new discoveries from entering museums, and are not in the public interest," added the academics who want the government to return to the "simple, well-tried system" practiced up to 2008.

Signatories include Professor Chris Stringer, recognized as one of the world's leading experts on Neanderthals at London's Natural History Museum and the head of archaeology at Oxford University, Helena Hamerow.

The issue has come to the fore now because the first special licenses governing the removal of skeletons are up for renewal.

Scientists can apply for extensions to hold bones for longer periods, but archaeologists contacted by Reuters said the process was needlessly bureaucratic and that the remains would have to go back in the ground anyway.

Professor Stephen Shennan, director of University College London's Institute of Archaeology, who also signed the letter, told Reuters it would hamper research into the population's origins.

"The study of ancient DNA, in particular, over the last few years, is transforming our knowledge of the early human populations of the British Isles and throwing all sorts of fascinating light on the history of populations in Europe as well," he said.

"The idea, in effect, of removing any possibility of carrying out further investigations on these bones is just a complete disaster -- it's not just a specialist interest."

Dr Mike Heyworth director of the Council for British Archaeology agreed. "It would be tragic," he told Reuters. "If this material becomes inaccessible to us we have lost that opportunity forever and that seems crazy."

The Ministry of Justice said in a statement the original review was undertaken in 2008 because the 1857 burial act lacked powers to authorize exhumation and retention for scientific purposes, citing health and decency laws.

"Archaeologists are welcome to apply to extend the time limit for reburial. A number have already done so and no such applications have been refused."