The men's remains had lain undiscovered for 93 years
Families of some British soldiers lost in action during World War I who thought their bodies had at last been found have had their hopes dashed.
Relatives of the soldiers thought to have been killed in the 1916 battle of Fromelles gave DNA samples after the bodies were exhumed last year.
But it has not been possible to identify all the 250 Allied soldiers found buried in the mass grave.
It has only been possible to say that three of the soldiers were British.
Sue Raftree, of the joint casualty and compassionate centre of the armed forces, which has been working to identify relatives of the soldiers, said the news was "bitterly disappointing".
She said: "The families are, I'm sure, quite gutted because we were always hopeful we would find some of them."
She said work to identify the soldiers and their relatives would continue, with more families researching their family trees in the hope they could help identify more of the remains.
Before the first bones were excavated from a field in northern France last May, the remains had lain undiscovered for 93 years since falling on the Western Front.
By January, more than 800 UK families who thought they might have lost a relative at Fromelles had given DNA samples in the hope of identifying the bodies.
But most will now be disappointed. Veterans Minister Kevan Jones admitted on Wednesday the effort to put names to bodies had been "a challenging task".
"We are disappointed that there was insufficient evidence to name British soldiers but I would like to thank the families for the support that they have all given to this project.
"Although no British soldiers could be named, I am pleased that we can confirm three having served with the British army.
"What is most important is that these men have all been laid to rest with the dignity and honour they deserve. The identification process will remain open for another four years and I hope that families will continue to make contact."
However, following the identification process, the names of 75 Australian soldiers found in the mass grave at Pheasant Wood have been released.
Of the 250 soldiers found, a total of 203 have been identified as Australians. It is thought about 1,500 British and 5,500 Australian troops fell in the battle.
All but one of the soldiers found in the mass grave have now been reburied in a new cemetery at Fromelles. The last will be buried on 19 July at a ceremony to mark the anniversary of the battle.