Adds background, updates prices

LONDON, April 28 (Reuters) - Raw sugar futures were lower on Monday with the market's focus on the expiry of the May contract later this week, while cocoa prices also fell.

SUGAR

* Raw sugar SBc1 fell 2.1% to 17.80 cents per lb by 1405 GMT. The May contract SBK5 expires on Wednesday.

* Dealers said a large delivery against May of about two million metric tons looked possible, with most of the sugar likely from Centre-South Brazil.

* They noted this would reinforce the sentiment that global supplies are currently ample.

* White sugar LSUc1 lost 2.1% at $503.10 a metric ton.

COCOA

* New York cocoa CCc2 fell 4.8% to $8,939 a ton in a sharp setback after climbing to a nine-week high of $9,500 on Friday.

* Dealers noted crop conditions were improving in the top grower Ivory Coast.

* Above average rainfall last week across most of Ivory Coast's main cocoa growing regions is expected to boost the development of the April-to-September mid-crop, farmers said on Monday.

* They also said the market was continuing to try to assess the extent to which a sustained rise in prices may be curbing demand, with earnings reports from Mondelez and Hershey this week likely to be closely watched.

* London cocoa LCCc2 fell 3.6% to 6,298 pounds per ton.

COFFEE

* Arabica coffee KCc2 rose 0.3% to $4.01 per lb after climbing to a seven-week high of $4.1050 on Friday.

* The market continued to derive support from the prospect of a fall in arabica production in Brazil this year and signs that demand has held up well despite a rise in retail prices.

* Arabica coffee speculators raised a net long position in the week to April 22, the Commodity Futures Trading Commission (CFTC) said on Friday.

* Robusta coffee LRCc2 lost 1.35% to $5,342 a ton.

(Reporting by Nigel Hunt; Editing by Vijay Kishore)

((nigel.hunt@thomsonreuters.com; +44 (0) 7990 561421; Reuters Messaging: nigel.hunt.thomsonreuters.com@reuters.net))