The UK is in danger of becoming one of the most monolingual countries in the world, which could harm its performance in the global economy and its "intercultural competence" and make it less attractive as a research hub.
This is the conclusion of a review of modern language provision in England commissioned by the Higher Education Funding Council for England.
The way to stem the decline is not to keep asking for more money but rather for universities to be more active in defending modern language tuition, according to the review, by Michael Worton, vice-provost of University College London.
Professor Worton criticises the higher education languages community for its "tendency to argue for sustainable salvation through ever more investment in teaching, research and widening participation/outreach activities".
Languages already receive "substantial investment" in these areas, he argues, and universities could do more themselves to make languages a priority.
Universities should be promoting the value of languages, including explicit references to languages in their international strategies and aligning their language departments with their missions, he says.
The review identifies a tension between the concept of language as a single discipline and the diversity of provision in different languages across the sector.
"It will be important to the future vitality of language study to ensure that the sector is able to come together to publicly acknowledge this tension - and to find ways of conceptualising it in a positive light," Professor Worton says.
Academics should be looking to collaborate across languages, he suggests, perhaps by sharing online teaching resources or through advocacy for language study within an institution.
The professor points to his own university's use of its admission policy as a means of encouraging language study. From 2012, all UCL applicants, regardless of discipline, will need to have a GCSE qualification or equivalent in a modern foreign language.