Cambridge and Oxford are among the most prestigious universities in the world, according to new international rankings Tuesday to other UK institutions are losing ground, it was announced here. A new global league table shows that the two top universities remain part of an elite group of "super brands". They were placed third and fourth respectively in the latest Times newspaper Higher Education (THE) World Reputation Rankings, with Oxford moving up two spots from sixth last year. The rankings measure the power of university brands, based on the opinions of senior academics. But researchers warned of a polarisation between the very top institutions in the UK, and the rest, amid increasing competition from Asian nations. The UK has lost three universities from the top 100 in the last two years, the rankings show. The latest table reveals that Leeds University has dropped out of the top 100, joining Sheffield University and the London School of Hygiene and Tropical Medicine, which lost their places last year. Other UK universities are faring better. Bristol University has clung on to a top 100 spot, at the bottom in the 91-100 group, while Manchester came 47th, putting it in the top 50 for the first time. Edinburgh University - the only Scottish institution in the top 100 - rose three places to 46th. University College London rose one place to 20th, and the London School of Economics increased four places from 29th to 25th. Overall, the UK had nine universities in the top 100, compared to 12 two years ago. Only the United States had more institutions into top 100 this year - 43 in total - with Harvard taking first place in the rankings, and Massachusetts Institute of Technology in second.