The backlash against Donald Trump’s trade fight grew on Wednesday as steel users challenged the tariffs in court and carmakers warned of a surge in prices if the US president delivered on threats to extend them to more valuable auto imports.

　　美国总统唐纳德特朗普关税政策激起的反对声浪周三继续发酵，钢铁用户就这些关税向法院提起诉讼，汽车制造商则警告称，如果美国总统兑现威胁，将加征关税的范围扩大至价值更高的进口汽车，汽车价格将大幅上涨。

　　In the most significant legal challenge to Mr Trump’s trade policies, the American Institute for International Steel said it had lodged an action in the US Court of International Trade to have the 1962 statute that the president used to impose steel tariffs ruled unconstitutional.

　　美国国际钢铁协会表示，它已向美国国际贸易法院提起诉讼，状告特朗普对钢铝加征关税所依据的1962年法律违宪。这是目前为止对特朗普关税政策最大的法律挑战。

　　The president last year invoked a provision known as “Section 232” of the law to launch an investigation into whether steel and aluminium imports posed a threat to US national security. Last month he launched a similar probe into imports of cars and parts from worth more than $330 billion last year.

　　特朗普去年根据这项法律的“第232条”对钢铝进口是否对美国国家安全构成威胁展开调查。他于上月对美国去年从全球进口的总价超过3300亿美元的汽车和汽车零部件发起类似调查。

　　The challenge comes as pro-trade Republicans in Congress, backed by the US Chamber of Commerce and other business groups, seek to roll back the law and rein in the president’s ability to impose further tariffs. They have pointed to what they say is the potential economic damage and concerns of companies over escalating trade wars with China and the EU.

　　美国国际钢铁协会发起这一挑战，正值美国国会内部的“亲贸易派”共和党人士在美国商会和其他商业团体的支持下，设法限制这项法律的适用范围、约束总统进一步加征关税的能力。他们指出，他们认为关税会给经济带来潜在损害，而且企业对美国与中国和欧盟贸易战升级感到担忧。

　　Automakers have said Mr Trump’s plans to impose tariffs on auto imports could raise prices of imported vehicles by as much as $6,000 per car and raise prices of locally made vehicles.

　　与此同时，汽车制造商表示，特朗普对进口汽车征收关税的计划，可能会使每辆进口车的价格上涨高达6000美元，并推高国产车的价格。

　　The Alliance of Automobile Manufacturers, which represents domestic and international car companies, has said that buyers of imported cars would face an average $5,800 price rise from a 25 per cent tariff.

　　代表国内和国际汽车公司的汽车制造商联盟指出，如果征收25%的关税，进口车买家将平均面临5800美元的涨价。

　　“If this investigation leads to tariffs, retaliation against US exports is inevitable,” he said. “Substantial tariffs against major US auto exports have in fact already been announced, placing American auto workers on the front lines of this trade conflict,” he added, in an apparent reference to EU tariffs against Harley-Davidson motorcycles.

　　“如果调查导致加征关税，对美国出口产品的报复将不可避免，”他补充说。“对美国主要出口机动车征收的高额关税实际上已经宣布，这让美国机动车工人站到了这场贸易冲突的前线，”他说，明显指的是欧盟对哈雷戴维森摩托车征收的关税。

　　Ten of the 14 auto companies producing vehicles in the US today were based overseas, he said.

　　他说，目前在美国从事汽车生产的公司有14家，其中10家为海外公司。

　　If other countries retaliate, job losses could climb to 624,000, the group said.

　　该机构表示，如果其他国家采取报复行动，失业人数可能会升至62.4万人。