HANOI, Oct 28 (Reuters) - Sharp declines in Vietnam's domestic coffee prices, of as much as 13 percent in the past week, have prompted some exporters to delay shipments until November to escape losses, traders said on Tuesday.

   Vietnam , the world's second-largest coffee producer after Brazil , has started harvesting its 2008/2009 crop and there should be ample supply when the process peaks in two weeks.

   Traders in Vietnam said robusta prices this week dropped 13 percent from a week ago, to around 22,500 dong ($1.36) per kg  from 26,000 dong last Tuesday, following sharp falls in London and the prospect of abundant supplies from the current harvest.

   Dealers said they had not heard of any defaults, as in rival producer Indonesia , however.

   "The sellers were asking to delay shipment to next month," a trader at a foreign firm in Ho Chi Minh City said, but declined to give details.

   "No one has defaulted yet but if November prices go down further, they will lose a lot more," said a trader in Buon Ma Thuot, the capital of Daklak province, Vietnam 's top coffee growing area.

   Indonesian exporters have delayed shipments of at least 30,000 tonnes of beans to various buyers and could default on delivery after a sharp drop in London futures prices, dealers said [ID:nSP195414].

   A farmer in Buon Ma Thuot said at the current price of around 23,000 dong per kg, and given a cash cost of 18,000 dong, he could still make a profit of 20 percent.

   Traders said discounts to London's benchmark January <LDKF9> robusta futures were being offered at around $190 a tonne, versus $150 last week, putting Vietnam's spot quotations at $1,414 a tonne, free on board (FOB), on Tuesday <COFFEE/ASIA1>.

   Vietnam had sufficient coffee beans for delivery from the previous and current crops, another Ho Chi Minh City trader said.

   "The new crop beans have very good quality and supply is ample. It is just the problem with pricing that may cause some delays," he said.

   Prices in the Central Highlands coffee belt have fallen about 27 percent in the past month from 32,500 dong in the week ending Sept. 27. ($1=16,515 dong)