$ETH The dollar staged a broad retreat on Thursday, as investor gloom over the lack of progress towards defusing the U.S.-China trade war reasserted itself following an interlude of optimism the previous day.U.S. assets, including the dollar, rallied on Wednesday after U.S. President Donald Trump backed down from threats to fire the head of the Federal Reserve and appeared to soften his stance on China.Treasury Secretary Scott Bessent said separately that the de facto embargo on U.S.-China trade was unsustainable, but that the U.S. would not move first in lowering its levies of more than 100% on Chinese goods.By Thursday, those dollar gains had unravelled. China said there had been no negotiations on the economy and trade and it urged the U.S. to lift all unilateral tariff measures if it really wished to resolve the issue, leaving investors roughly where they were earlier in the week in terms of clarity.The yen led the charge higher, leaving the dollar down 0.71% on the day at 142.395, but still above the 140-mark breached last week.