The potential economic benefits for the UK tourism industry from the London 2012 Olympics are under threat because of a poor strategy and underfunding, the Tourism Alliance has said.

The Alliance says that underfunding and cuts to marketing budgets could make it impossible to meet the suggested £2bn windfall as a result of the Games.

Kurt Janson, the Tourism Alliance's policy director, told Leisure Opportunities that a lack of strategic thinking and funding from the Department for Culture, Media and Sport (DCMS) was putting pressure on the industry.

"Discounting investment from the Welsh and Scottish governments and the Regional Development Agencies, the DCMS is responsible for only £55m in dedicated funding. This isn't enough to deliver the benefits expected," Janson said.

"We would like to see a further £20m from the DCMS, to be matched by the industry, which could be expected to deliver in the region of one million extra visitors."

The warning follows a positive recent report from the Nation Brands Index on behalf of VisitBritain, which indicated that visitors were more likely, and likely to stay for longer, as a result of the Olympics.

Despite these optimistic findings, host nations have often struggled to maintain tourism increases after Olympic Games. Industry insiders believe that 2012 may be little different, unless there is an increase in funding.