People have been banned from a stretch of Eastney beach by defence giant Qinetiq.
The firm has put 'keep out' signs up on a section of beach it owns which is traditionally used by naturists.
It is the latest move in a long-running battle between Qinetiq and Portsmouth City Council over a planned development of 131 homes on the Fraser Range land overlooking the beach.
The two sides have been locked in a legal dispute about the rights over a stretch of land leading to the development site.
Qinetiq offered guaranteed public access to the beach if city leaders signed a deed which would allow them to widen the access road - meaning the flats scheme could go ahead. But so far the two sides have not been able to reach an agreement.
Now Qinetiq says it is looking at alternative uses for the site, which could see it returned to its former use as employment land. They say restricting access to the beach is part of their preparation - and keeps out vandals.
The move has angered beach-goers. Mike Houlsby, from Eastney Naturist Group, said: 'I think it is the wrong thing to do and sends out the wrong message. It doesn't seem like commercial negotiations, it is more like a fit of pique.'
As reported, naturists fought against the development amid fears Qinetiq will ban them from the beach if it goes ahead.
Eastney ward councillor Luke Stubbs, Conservative, said: 'Any redevelopment of the land is years away, so what harm is there in letting people use the area in front of what are now empty buildings?'
The firm says it will still guarantee public access to the beach if the council signs the deed allowing the residential development to move forward.
Spokeswoman Claire Scotter said: 'Qinetiq included a legally water-tight agreement for open public access to the beach within the deed in July 2008. However the cabinet has refused to grant the deed on a number of occasions, against the advice of its own legal team. The decisions of the cabinet are driving us to consider the site for re-use for employment.'
Council leader Gerald Vernon-Jackson said: 'I understand we have done everything we should. I understand we had come to a conclusion with them which guaranteed public access. The council has stuck to it so I hope they do as well.'
PUBLIC DONATED BEACH TO HELP WITH WAR EFFORT
The beach at Eastney was originally handed over to the Ministry of Defence by the people of Portsmouth so defences could be built to protect the Solent during the Second World War.
After the war, the beach remained property of the MoD and passed to Qinetiq when it developed as a private company.
It has never been officially designated a nudist beach, although it has been used by naturists dating back more than 40 years.
When Qinetiq earmarked the land for development it sparked fears nudists would be banned.
The Eastney Naturist Group has always maintained it was unfair that they could be prevented from using a beach which originally belonged to the public.
Qinetiq says it has no power to designate the land for use by naturists, but until now has said it can be used by all members of the public. The firm now says if uses the land for employment it would not condone naturism as it could offend employees.
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