* Robusta moves lower, hovers above six-month low
* Arabica consolidates after sharp losses
* Ivory Coast customs officials block cocoa products exports
(Adds quote, details, updates prices)
LONDON, Nov 2 (Reuters) - Robusta coffee futures on Liffe eased on Friday but prices held above a six-month low set earlier this week as the focus remained on Vietnam's crop which is expected to be large but slightly below last season.
Arabica coffee futures on ICE edged up from a four-month low set during the prior session while cocoa also advanced and sugar was little changed.
January robusta coffee futures fell $5 or 0.3 percent to $1,979 a tonne at 1510 GMT. The contract touched $1,965 on Wednesday, the lowest level for the second-month since April, under pressure from ample Vietnamese supplies.
``Even the cash prices in Vietnam are coming off and so (Vietnamese) production is having an impact on futures markets as well. I think there could be some downward pressure as we're only just at the beginning of the harvest,'' Macquarie analyst Kona Haque said.
Vietnam's 2012/2013 coffee output will decline 15 percent due to adverse weather following a bumper harvest in the last season, an official of a Vietnamese export firm said on Friday, reaffirming an earlier industry forecast.
December arabica coffee futures were up 0.95 cent or 0.6 percent at $1.5440 per lb. The contract hit $1.5280 on Thursday, the lowest level for the front month since June 22.
``It's just a technical bounce as prices have fallen quite sharply this week, below the $1.65 mark. At these levels it could be some bargain hunting roasters adding coverage,'' Haque said.
Coffee exports from Honduras rose 231 percent in October, the first month of Central America's 2012-13 coffee season, to 59,111 60-kg bags compared with the same month last year, the country's coffee institute, IHCAFE, said on Thursday.
ICE December cocoa was up $18 or 0.7 percent at $2,438 per tonne as traders continued to keep a close watch on the early progress of main crop harvests in West Africa.
Ghana's cocoa purchases hit 86,028 tonnes by Oct. 19 since the season started on Oct. 12, down 42 percent from the same period a year ago, Cocobod data showed on Thursday.
Dealers said the number was lower than expected and was helping to underpin the market.
``People are looking at recent Ghana purchases which are further behind last year, but we have to compare apples to apples - considering the overflow from previous season, purchases in the first week of last year would have been very strong,'' said a London-based broker.
``If we've got continued weak purchases for the next two or three weeks then potentially there is an issue and they may have oversold the crop.''
Weak purchase figures, if maintained, may indicate production may reach the level expected when Ghana embarked on its pre-harvest sales programme, raising the possibility the world's number two producer may have oversold its crop.
Across the border in Ivory Coast customs officials were blocking the export of 72,000 tonnes of cocoa products from the recently-ended 2011-12 season due to confusion over tax rates, exporters and customs officials said on Friday.
Dealers said this, as well as an outbreak of fungal black pod disease in Ivory Coast, could push up prices.
``It could well do (provide support) as it's 72,000 tonnes. There is so much bullish news at the moment it's hard for the market to go anywhere but onwards and upwards from here, in the short term anyway,'' a UK-based broker said.
Meanwhile, in Asia cocoa butter ratios jumped to their strongest in two years as consumers scrambled to stock up to meet festive demand, but a lack of interest prompted grinders to cut the price of powder, dealers said on Friday.
Benchmark Liffe March cocoa futures were up 13 pounds at 1,573 pounds per tonne.
March sugar futures were unchanged at 19.38 cents a lb as the market continued to consolidate just above a six-week low set earlier this week.
The contract fell to 19.18 cents on Wednesday, the lowest level for the front month since Sept. 21.
Dealers said an anticipated substantial global surplus in 2012/13 was keeping the market on the defensive while producers now appeared to be willing to sell at lower prices.
December white sugar on Liffe dipped $2.60 or 0.5 percent to $536 per tonne.
(Additional reporting by Nigel Hunt; Editing by Alison Birrane and David Cowell)