India's Gukesh is youngest world chess champion - at 18

Indian teenager Gukesh Dommaraju has become the youngest chess world champion by beating defending champion Ding Liren of China in a dramatic turn of events in the last game of a 14-game match in Singapore.

The 18th world champion is, at the age of 18, four years younger than Garry Kasparov, who had been the previous holder of that accolade when he beat Anatoly Karpov in 1985.

Gukesh won Thursday's game with the black pieces after Ding wilted under pressure and blundered in what commentators considered to be a comfortable position, snatching the title with a final score of 7.5-6.5.

Ding, whose form has plummeted since he beat Russian Ian Nepomniachtchi to claim the crown in 2023, had not won a long-time format "classical" game since January and largely avoided top events in a bid to improve.

But the Chinese player regained confidence after a surprise win in the opening round of the match and, following two wins for Gukesh and eight draws, had evened the score in round 12 with a victory which was acclaimed by several commentators.

The match was a 14-round long-time "classical" event with a prize fund of $US2.5 million ($A3.9 million).

Gukesh had qualified in April by winning the Candidates tournament.

World No.1 Magnus Carlsen, who had been world champion since 2013, relinquished his title in 2022, citing a lack of motivation.