Benchmark Tokyo rubber futures ended down 2.9 percent on Friday, after hitting a near two-week low earlier in the session, led by Shanghai futures on news that the world's top producers will not curb exports, brokers said.
Shanghai futures fell more than 5 percent after Thailand's agriculture minister said the International Tripartite Rubber Council (ITRC), which represents the world's top natural rubber producers, will now closely monitor trends in rubber prices, adding that Vietnam would join the group.
Present members of the council produce nearly 70 percent of the world's natural rubber, and with Vietnam, the council will account for almost 80 percent of global production.
The market also came under pressure after North Korea fired another missile overJapan on Friday, demonstrating Pyongyang's defiance against intensifying U.N. sanctions.
The Tokyo Commodity Exchange rubber contract for February delivery finished down 6.7 yen at 221.2 yen ($2.00) per kg. For the week, it fell 2.1 percent.
Japanese markets are closed on Monday for a national holiday.
The most-active rubber contract on the Shanghai futures exchange for January delivery fell 855 yuan to finish at 15,725 yuan ($2,402) per tonne. On reports of the council's decision, it plunged more than 5 percent to a one-month low of 15,680 yuan.
Rubber inventories in warehouses monitored by the Shanghai Futures Exchange rose 2.0 percent from last Friday, the exchange said on Friday.
The front-month rubber contract on Singapore's SICOM exchange for October delivery last traded at 159.70 U.S. cents per kg, down 6.6 cents. ($1 = 110.6300 yen) ($1 = 6.5471 Chinese yuan)