Aberdeen University remains in the world's top 200 universities despite dropping down an international league table.

The institution fell 17 places from 141 last year to 158 in this year's listings.

Aberdeen was one of four Scottish universities to see their standing fall in the annual table.

Edinburgh has the highest ranked university in Scotland but it has dropped out of the world's top 20 to sit at 23, down from 19 last year.

The highest ranking university in the UK is Cambridge at number five, down one from last year, closely followed by Oxford in sixth place.

Falling university resources and increasing competition from other parts of the world are behind the Scottish results, researchers claim.

The four best universities in the world are all US based with the Massachusetts Institute of Technology named in the number one spot.