British universities have been told that their "special relationship" with US institutions may be lost unless urgent action is taken to strengthen transatlantic links.
A report published this week by the British Council, UK-US Higher Education Partnership: Realising the Potential, finds that only a "limited number" of UK universities have created successful partnerships with institutions in America.
Meanwhile, underinvestment in the relationship has encouraged competitors to move in. In the delivery of joint degrees with US institutions, the UK has fallen behind China, France, Germany, Mexico and South Korea, the report says.
The US academy is keen to diversify its international relationships, particularly by working with universities in the Asia-Pacific region, it adds.
The report also warns that the primacy of science, technology, engineering and mathematics (STEM) could put the UK in a difficult position.
Their prominence will lead US academics to form stronger ties with Asia rather than Europe, it predicts.
US universities have identified the social sciences and the biosciences as priority areas for joint research with the UK, but not STEM, which is a UK priority.
It identifies a "virtuous circle" for improving relations, in which research partnerships and faculty links lead to new forms of teaching collaboration and international studentships, which in turn encourage research partnerships.
The British Council claims a close relationship with the US is "vital" for UK research. It calls for greater investment in marketing the UK overseas and says the British sector must better understand its American counterpart. It is advised to encourage research co-operation, work with a larger number of US institutions and recruit more young American researchers and students.
Pat Killingley, director of higher education at the British Council, said: "The global environment is changing, and both UK and US institutions must adjust if they are not to lose the great advantages they have enjoyed for decades by working so closely together."