The Department for Culture Media & Sport and the Ministry of Defence have published guidance on how existing policies and legislation apply to historic military wreck sites - see it here
Although this guidance focuses on military wrecks, it re-affirms general government policy with regard to underwater cultural heritage and sets out key management principles. In particular, it confirms the UK Government’s adoption of the principles set out in the Annex to the UNESCO Convention on the Protection of Underwater Cultural Heritage 2001 as best practice in the archaeological and cultural management of underwater sites and artefacts.