Benchmark Tokyo rubber futures snapped a four-day losing streak on Friday on bargain-hunting, but posted a fall for the week amid concerns over rising stockpiles despite the start of a seasonal decline in production due to wintering.
However, the gains were limited as US President Donald Trump's threat of new tariffs on China reignited fears of a trade war between the world's two biggest economies.
Rubber is tapped year round, but latex output drops during the dry wintering season, when trees shed leaves.
Tokyo Commodity Exchange (TOCOM) futures, which set the tone for rubber prices in Southeast Asia, have barely recovered from a 17-month hit on March 26 as Japanese stocks stood over 15,000 tonnes, compared with below 5,000 tonnes a year earlier.
The agreement by the International Tripartite Rubber Council (ITRC) - which consists of Thailand, Indonesia, and Malaysia - to cut natural rubber exports to stabilize global prices expired at March-end, but the group has so far not agreed on a follow-up deal.
"A rising stockpile at a time of an ongoing wintering period is the biggest stumbling block for rubber prices," said a Japanese trading source.
The Tokyo Commodity Exchange rubber contract for September delivery finished 3 yen higher at 179.3 yen (US$1.67) per kg, ending the week with a 2.6% decline.
The front-month rubber contract on Singapore's SICOM exchange for May delivery last traded at 134.5 US cents per kg, up 0.5 cent.
Malaysia's rubber products exports fell 4.1% in February from a year earlier to 2.0 billion ringgit (US$516.80 million), government data showed on Thursday.
Shanghai futures exchange was closed for a public holiday.
Source: The Edge Markets