ONE of Scotland's leading university principals is to step down after 15 years in the post.

Professor Sir Timothy O'Shea, principal of Edinburgh University, who was appointed in 2002, will leave in September next year at the age of 68.

During his period at the helm Sir Tim has presided over a significant period of expansion and internationalisation of the university - which is Scotland's largest.

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The university has regularly been ranked as one of the top 25 universities in the world and has also cemented its place as one of the UK's foremost research intensive universities, ranked fourth in Britain for the quality and breadth of its research.

Sir Tim has also ensured that Edinburgh has been a pioneer in distance and e-learning with the institution becoming the first in the UK to introduce Massive Open Online Courses to audiences around the world.

He has also been a passionate advocate of social inclusion and widening access to the institution as well as promoting links with business. Between 2010 and 2015 the university was responsible for the formation of 184 new companies, with 44 created in 2015 alone.

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He said: "It has been an honour and a privilege to serve as principal of Edinburgh University and I am extremely proud of what we as an institution have achieved over recent years.

"The success and growth that we have enjoyed have only been possible thanks to our very gifted students and highly talented staff, as well as the tremendous backing we've received from our alumni, supporters and friends across Scotland, the wider UK and the world."

John Swinney, the Education Secretary and Deputy First Minister, paid tribute to Mr O'Shea's role in helping cement the reputation of Scottish universities across the globe.

He said: "Under Sir Tim's leadership, Edinburgh University has built on its reputation as one of the world's great universities and is widely regarded as a powerhouse of ideas and innovation across the breadth of academic endeavour, bringing distinction and talent to Scotland."

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Born in Hamburg in British-occupied Germany in 1949 to an Irish father and a German mother he grew up bilingual, but with little family emphasis on the importance of school.

When his family moved to London a few years later he attended an Irish Catholic primary school and then a Protestant grammar.

Sir Tim, who earns a salary of £227,000, is unusual in the university sector in that he has continued to refuse a pay rise over the past few years.

In an interview with the Herald last year he said: "I think I am well paid and I think I do a good job, but it has been my decision not to have a pay rise.

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"I felt that at a time of economic austerity it was very difficult if my colleagues were not getting pay rises. Each year there has been a suggestion for a rise, but I have declined. It is the context. I wouldn't really be comfortable taking a pay rise if the majority of my colleagues were not."

Often outspoken, Sir Tim courted controversy in recent weeks after publicly backing a vote to stay in the EU. In a joint open letter with student leaders, Sir Tim argued that the UK's place in the EU brings "many benefits" to the university.