The Office of Fair Trading has published a report which shows that 38 per cent of Britain's infrastructure is owned by foreign companies and investors.
The report shows that 42 per cent of British infrastructure is owned by publicly listed companies, both from Britain and abroad, whilst 18 per cent of infrastructure is publicly owned.
The strong presence of foreign firms was described as "very positive" by the OFT as they claim market competition brings down costs and places greater discipline in companies.
The OFT said it would be willing to intervene in areas of British infrastructure where there are "long-term barriers to entry" and constraints on potential competition.
Heather Clayton, Senior Director of OFT's Infrastructure Group, said, "This stock-take pulls together for the first time and in one place information on who owns the UK's economic infrastructure.
"It provides clarity and greater certainty to businesses and investors on when we might consider intervening in Infrastructure sectors. Alongside this, our report should have wider benefit to government and other bodies responsible for ensuring competitively provided infrastructure contributes to economic growth.
"The key aims of the stock-take were to map ownership and control across the economic infrastructure sectors such as ports, airports, energy and water networks, assess how ownership of infrastructure affects outcomes for consumers in these markets and examine the different forms of ownership."