The country's two oldest universities have topped the latest global rankings in specific subject areas.

Nanyang Technological University (NTU) has overtaken the Massachusetts Institute of Technology (MIT) to become the world's leading institution for the study of materials science, according to a league table compiled by Britain-based Quacquarelli Symonds (QS), a higher-education analysis firm.

"Materials science is the heart of all technological innovation and this will only become more important with the world focus on sustainability and the ageing population," Professor Lam Yeng Ming, chair of NTU's School of Materials Science and Engineering, told The Straits Times.

"This year's ranking is a confirmation that with Singapore's foresight to invest strongly in research in materials science, coupled with very driven faculty and researchers, we can be the world leader in an impactful area."

Last year, NTU's materials science programme was ranked third out of about 400 programmes worldwide.

QS also placed the National University of Singapore's (NUS) petroleum engineering programme at No. 1, a position it also attained last year out of 151 contenders.

Overall, NUS ranked 11th out of 1,000 universities, while NTU came in 13th. Last year, both universities tied for 11th place.

"The consistent improvements made by Singaporean institutions in our rankings are the result of a decade of investment and strategising," said Mr Ben Sowter, QS' senior vice-president of professional services. "It was in 2010, after all, that the Singaporean Government inaugurated the Singapore universities fund, with a view to avoiding the sort of downturn-driven real-terms funding cuts that have beleaguered universities across the world."

The QS analysis also found Singapore to be the fourth-best higher-education system in the world after the United States, Britain and Switzerland, and first in Asia based on its share of programmes in the top 10 globally.

"Singapore is home to more world-class programmes than any other Asian higher-education system: It has four times as many top-10 programmes as China's six and eight times as many as Japan's three," the firm added.

The two local universities had 24 degree programmes in the top 10 globally - 16 from NUS and eight from NTU.

Several degree courses made large jumps in the rankings. NUS' computer science and information systems course shot up from 12th last year to rank fourth this year, while NTU's mechanical, aeronautical and manufacturing programme jumped to fifth place from 11th.