"The European Union and its single market are indivisible", the former Luxembourg premier said when asked about Trump's bid for bilateral deals.
He is also aiming to use claims of national security to gain leverage in negotiations, the Journal reported.
Trump imposed duties of 25 percent on steel imports and 10 percent on aluminum in March, but gave temporary exemptions to the E-U.
The Alliance of Automobile Manufacturers, whose members include General Motors Co, Volkswagen AG and Toyota Motor Corp, said it plans to issue the warning at a public hearing on Thursday.
Peter Welch of the National Automobile Dealers Association says there's no basis to the argument that auto imports are a national security threat to the US and he warns that the tariffs would inflate the cost of vehicles for American consumers.
"Higher auto tariffs will harm American families and workers, along with the economy" and "would raise the price of an imported vehicle almost US$6,000 and the price of a USA -built vehicle US$2,000", the group said in its testimony released on Wednesday.
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A MusiCall intercom, floral wallpaper, wood paneling and stone fireplace have been meticulously maintained. The Los Angeles Times reported that Violet and George McCallister bought the home in 1973 for $61,000.
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DFSR's Chris Durell and Doug Norrie are on the podcast breaking down the 147th Open Championship for DraftKings and FanDuel . The two names atop the leaderboard are far from what anyone expected, which is not uncommon for early in a major.
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There are also deep fears US levies would harm the overall Canadian and American economies because collateral damage would reach well beyond the critical, thriving auto sector.
A study by the Center for Automotive Research also released Thursday estimated auto demand will fall by between 493,600 and two million vehicles, resulting in the loss of 82,000 to almost 750,000 auto manufacturing jobs.
No automaker or parts company has endorsed the tariffs, and they have pointed to near-record sales in recent years.
Many automakers opted not to testify at the hearing because they believe Trump can not be swayed from his decision to impose the tariffs. "We have to - including cars". "Including cars, cars is the big one". "And you know what we're talking about with respect to cars and tariffs on cars".
European Commission President Jean-Claude Juncker will visit President TrumpDonald John TrumpShocking summit with Putin caps off Trump's turbulent Europe trip GOP lambasts Trump over performance in Helsinki Trump stuns the world at Putin summit MORE at the White House next week, following the USA leader's blistering criticism of critical North Atlantic Treaty Organisation allies and the European Union during a week-long trip to Europe.
The Commerce Department said earlier this week it aimed to complete the investigation "within a couple months".