Bones and skulls from ancient settlements will be reburied and lost to science under controversial legislation that threatens to cripple archeological research

Human remains from Stonehenge and other ancient settlements will be reburied and lost to science under legislation that threatens to cripple research into the history of humans in Britain, a group of leading archaeologists says today.

In a letter addressed to the justice secretary, Ken Clarke, and printed in the Guardian today, 40 archaeology professors write of their "deep and widespread concern" about the issue.

The dispute centres on legislation introduced by the Ministry of Justice in 2008 which requires all human remains excavated at digs in England and Wales to be reburied within two years, regardless of their age. The decision, which amounts to a reinterpretation of law previously administered by the Home Office, means scientists have too little time to study bones and other human remains of national and cultural significance, the academics say.

"Your current requirement that all archaeologically excavated human remains should be reburied, whether after a standard period of two years or a further special extension, is contrary to fundamental principles of archaeological and scientific research and of museum practice," they write. Signatories include Chris Stringer, head of human origins at the Natural History Museum in London; Stephen Shennan, director of University College London's archaeology institute; and Helena Hamerow, head of archaeology at Oxford University.

The ruling applies to any pieces of bone uncovered at around 400 dig sites, including the remains of 60 or so bodies found at Stonehenge in 2008 that date back to 3,000BC. Archaeologists have been granted a temporary extension to give them more time, but ultimately the bones will have to be returned to the ground.

The arrangements, the archaeologists say, may result in the squandering of future discoveries at sites such as Happisburgh in Norfolk, where excavations are continuing after the discovery of stone tools made by early humans 950,000 years ago.

"If human remains were found at Happisburgh they would be the oldest human fossils in northern Europe and the first indication of what this species was. Under the current practice of the law those remains would have to be reburied and effectively destroyed," said Mike Pitts, editor of British Archaeology. "This applies to everything. If we were to find a Neanderthal fossil or a Roman skeleton, it would all have to be reburied."

Prior to 2008, guidelines allowed for the proper curation and study of bones of sufficient age and historical interest, while the Burial Act 1857 applied to more recent remains, such as those exhumed from the St Pancras Old Church cemetery to build the London Eurostar train terminal. The Ministry of Justice assured archaeologists two years ago that the ruling was an interim measure, but has so far failed to revise its decision.

Mike Parker Pearson, an archaeologist at Sheffield University, said: "Archaeologists have been extremely patient because we were led to believe the ministry was sorting out this problem, but we feel that we cannot wait any longer.

"Whereas we have museum collections of ancient and prehistoric human remains that have been dug up in some cases hundreds of years ago, we are about to lose all of the well-excavated, well-documented skeletal material that has been excavated since 2008," he added.

The ministry has no guidelines on where or how remains should be reburied, or on what records should be kept.

Removing the need to rebury ancient human remains within two years would give archaeologists the option to study excavated bones with new scientific techniques that constantly emerge from research laboratories, the letter says.

Remains from dozens of sites are immediately at risk of reburial, including eight bronze and iron age bodies found at Clay Farm in Cambridgeshire, 50 or so skeletons from the cemetery of a medieval hospital in Bawtry, South Yorkshire, and a remarkable Viking mass burial site excavated during work on the Weymouth relief road in 2009.

"The government is asking us to destroy important materials, not preserve them for future generations, a situation that is against its own heritage policies, contra to the public will and not in the interests of the general public at large," said Duncan Sayer, an archaeologist at the University of Central Lancashire.

"This is a law that was not designed for archaeology and is doing a considerable amount of damage, and because of it we may prevent people in the future from ever being able to explore their past because we have destroyed it."