(Bloomberg) -- The dollar’s downtrend may be set to resume.Hedge funds boosted net short positions in the greenback to the highest since April 2018 in the week through Jan. 12, according to data aggregated from the Commodity Futures Trading Commission. They also raised net bullish bets on the pound to the most since October while wagering on the euro and the Australian and New Zealand currencies to rise.The bets come as the world’s reserve currency enjoys a reprieve from a two-year slide after U.S. yields climbed to a 10-month high. A renewed bout of weakness in the dollar may amplify scrutiny of the incoming U.S. administration’s policy, with Treasury Secretary-designate Janet Yellen expected to declare that the authorities won’t seek a weaker currency to boost exports in her testimony on Tuesday.“The dollar is still likely to move lower over the course of the year,” Seamus Mac Gorain, head of global rates at JPMorgan Asset Management, said in an interview last week. “Many of the currencies which are more levered to global growth, particularly emerging market currencies” and the Aussie are set to strengthen, he said.The Bloomberg Dollar Spot Index has climbed over 1% since sliding to the lowest in almost three years this month. While the gains have fueled talk about a rebound, some including Goldman Sachs Group Inc. and investors in a Bank of America Corp. survey remain steadfast in forecasting a weaker greenback.“We continue to believe that the combination of high dollar valuations, low nominal and real rates, and a rapid recovery in the global economy will weigh on the greenback throughout 2021,” Goldman strategists including Danny Suwanapruti wrote in a Jan. 17 note.Yellen is expected to affirm the U.S.’s commitment to market-determined dollar value and give assurances that the U.S. won’t seek a weaker dollar for competitive trade advantage, the Wall Street Journal reported, citing President-elect Joe Biden transition officials familiar with her preparation for her confirmation hearing.The U.S. adopted a policy of favoring a “strong” dollar in 1995. While the mantra did evolve from one Treasury chief to another, no administration from then until the Trump years communicated, as the president did in 2017, that the dollar was “getting too strong.”“This is not the same as the strong-dollar policy of the past,” Khoon Goh, head of Asia research at Australia & New Zealand Banking Group Ltd., said of Yellen’s expected upcoming remarks. “A commitment to market-determined exchange rates implies that the new administration will be comfortable with further dollar weakness.”National Australia Bank Ltd. agrees.“We interpret Yellen’s view to mean the U.S. government is unlikely to stand in the way of an ongoing market-driven dollar depreciation,” said Rodrigo Catril, currency strategist at NAB in Sydney. There’s “no challenge to the current dollar downtrend.”(Adds comment from National Australia Bank Ltd. strategist in last paragraph)For more articles like this, please visit us at bloomberg.comSubscribe now to stay ahead with the most trusted business news source.©2021 Bloomberg L.P.