UK universities 'punch above weight' globally
Of the world's 100 most prestigious universities, 12 are in the UK, according to the 2015 Times Higher Education world reputation rankings.
The table is based on the views of a global panel of leading academics
Rankings editor Phil Baty urged careful protection and better funding for "real jewels in the UK's crown".
Researchers analysed responses from almost 10,000 academics to a survey carried out in December and January.
'Super-brands'
The academics invited to take part were chosen based on United Nations data to ensure an accurate reflection of the global distribution of scholars.
They were asked to nominate the best institutions in their field of expertise.
Top for reputation 2015
As in previous years, the top 100 is dominated by US institutions, with Harvard University in first place and 42 others taking up places lower down the table.
The UK's Cambridge University took second place and Oxford third, with Massachusetts Institute of Technology fourth, Stanford fifth and University of California Berkeley in sixth place.
Times Higher Education describes these as "an elite group of six US and UK 'super-brands' that stands head and shoulders above the rest".
'Clear vision'
Overall there were 12 UK universities in the top 100, up two from 2014:
- Imperial College London 14th
- University College London 17th
- London School of Economics 22nd
- Edinburgh University 29th
- Kings College London 31st
- University of Manchester 50th
Other top-ranked UK universities were:
- Durham
- Warwick
- Bristol
- London Business School
"It is clear from this latest research that the UK is punching well above its weight in higher education globally," said Mr Baty.
But he added "these incredibly valuable assets need to be carefully protected" and urged a "clear vision" from politicians on funding "as other nations invest heavily in their top universities".
"The UK's universities deserve, and desperately need, strong financial support," he said.
Nicola Dandridge, chief executive of Universities UK, said it was a real achievement that the UK retained the second strongest university system in the world "despite spending far less on it" compared with major competitors.
"That is why, ahead of May's general election, Universities UK is calling on all political parties to close this international funding gap, to support universities' international activities and to develop a sustainable student funding system in England," said Ms Dandridge.