* Widodo: trade war could be worse than global financial crisis
* Market falls spread from emerging markets to Wall St
* IMF says trade war to hurt global growth over next 2 years
* Inflaming tensions, China posts record U.S trade surplus
* China trade talks must cover currency, U.S. Treasury chief says
NUSA DUA, Indonesia, Oct 12 (Reuters) - Just in case any of the global central bankers and finance ministers gathered in Indonesia missed the message delivered repeatedly this week, the host nation said it again on Friday; everyone stands to lose if trade wars are allowed to escalate.
Indonesian President Joko Widodo didn't mention the United States or China, the world's two largest economies, but it was clear who he was talking about in an address to the plenary session of the International Monetary Fund and World Bank meetings on the island of Bali.
"Lately it feels like the relations among the major economies are becoming more and more like "Game of Thrones,"" Widodo said in a speech peppered with references to the HBO series about dynasties and kingdoms battling for power.
"Are we so busy fighting with each other and competing against each other that we fail to notice the things which are increasingly threatening, all of us alike, rich and poor, large and small," he said.
Poorer and populous emerging market countries like his are among the most vulnerable to the fallout from the ongoing U.S.-Sino tariff war, and rising U.S. interest rates that are drawing investors away and driving down currencies.
"All these troubles in the world economy, are enough to make us feel like saying: 'Winter is Coming'," Widodo said, using a phrase that characters in the popular fantasy series constantly repeat to refer to spectral dangers that could destroy them all.
With rivalry growing in the world economy, Widodo said "the situation could be more critical compared to the global financial crisis 10 years ago."
The market ructions have now cascaded through to developed markets with Wall Street extending a slide into a sixth session on Thursday amid the trade war fears.
The United States and China have slapped tit-for-tat tariffs on hundreds of billions of dollars of each other's goods over the past few months.
The tariffs stem from the Trump administration's demands that China make sweeping changes to its intellectual property practices, rein in high-technology industrial subsidies, open its markets to more foreign competition and take steps to cut a politically sensitive U.S. goods trade surplus.
Rubbing salt in U.S. wounds, China reported on Friday an unexpected acceleration in export growth in September and a record $34.13 billion trade surplus with the United States.
CHINA TRADE TALKS MUST INCLUDE YUAN: MNUCHIN
In an interview with Reuters, U.S. Treasury Secretary Steven Mnuchin said that he told China's central bank chief that currency issues need to be part of any further U.S.-China trade talks and expressed his concerns about the yuan's recent weakness.
Mnuchin also said that China needs to identify concrete "action items" to rebalance the two countries' trade relationship before talks to resolve their disputes can resume.
The U.S. Treasury chief and People's Bank of China Governor Yi Gang extensively discussed currency issues on the sidelines of the meetings in Bali.
Mnuchin's comments on China's currency come ahead of next week's scheduled release of a hotly anticipated Treasury report on currency manipulation, the first since a significant weakening of yuan began this spring.
Meanwhile, the chairman of a meeting of finance leaders from the Group of 20 leading industrialized and emerging economies admitted that the trade tensions within the group could only be solved by the countries directly involved.
"The G20 can play a role in providing the platform for discussions. But the differences that still persist should be resolved by the members that are directly involved in the tensions," Nicolas Dujovne, Argentina's Treasury Minister, told a news conference after chairing the G20 meeting in Bali.
More than 19,000 delegates and other guests, including ministers, central bank heads and some leaders, were attending the IMF-World Bank meetings, and Widodo asked them to "cushion the blows from trade wars, technical disruption and market turmoil."
"I hope, you will each do your part to nudge our various leaders, in the right direction," Widodo said, adding that "confrontation and collision impose a tragic price."
The IMF's twice-yearly report on the Asia Pacific region, released on Thursday, warned that the market rout seen in emerging economies could worsen if the Federal Reserve and other major central banks tightened monetary policy more quickly than expected.
At Friday's plenary, IMF managing director Christine Lagarde estimated that the escalation of current trade tensions could reduce global GDP by almost one percent over the next two years.
IMF forecasts of global economic growth for both 2018 and 2019 were cut to 3.7 percent, from 3.9 percent in its July forecast.
"Clearly, we need to de-escalate these disputes," Lagarde told the plenary session.
(Additional reporting by David Lawder, Gayatri Suroyo and Yawen Chen; Editing by Simon Cameron-Moore)