LONDON, Dec 29 (Reuters) - Robusta coffee futures on ICE eased slightly on Friday, slipping back from last week's more than 15-year high, but remained on track to post an annual gain of more than 60%.

Arabica coffee, sugar and cocoa markets were also set to post annual gains.

COFFEE

* March robusta coffee LRCc2 fell 0.9% to $2,910 a metric ton by 1135 GMT, slipping back from a more than 15-year high of $2,970 set last week.

* Robusta coffee prices are on a track for an annual gain of 62% boosted by a decline in exports from top producer Vietnam and strong demand as roasters increase the proportion of cheaper robusta in some blends at the expense of arabica.

* Coffee exports from Vietnam are estimated to have fallen 9.6% in 2023 from a year earlier to 1.6 million metric tons, government showed on Friday.

* March arabica coffee KCc1 fell 0.5% to $1.9705 per lb.

* Arabica coffee prices are on track for an annual gain of 18%.

COCOA

* March London cocoa LCCc1 fell 0.2% to ​3,543 pounds a ton.

* London cocoa prices on a track for an annual gain of 72% buoyed by tight supplies with a third successive global deficit widely forecast for the current 2023/24 season.

* March New York cocoa CCc1 fell 0.3% to $4,242 a ton.

* New York cocoa prices are on track for an annual gain of 63%.

SUGAR

* March raw sugar SBc1 lost 0.05% to 21.75 cents per lb.

* Raw sugar prices are on track for an annual gain of 9% with poor crops in India and Thailand partially offset by strong production in Centre-South Brazil.

* March white sugar LSUc1 was down 0.1% at $621.50 per metric ton.

* White sugar prices are on track for an annual gain of 12%.

(Reporting by Nigel Hunt; Editing by Kirsten Donovan)

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