President Donald Trump’s threatened trade tariffs are like a “thunderstorm” facing Europe, according to the head of a German industry body.

“There is a thunderstorm coming from the west of the Atlantic, and we should all prepare for this in Europe and we should work on these issues (around trade),“ Joachim Lang, director general of the Federation of German Industry (BDI), told CNBC’s “Squawk Box” on Monday.

Trade relations between the U.S. and Europe, as well as China, Canada and Mexico, are at a low point several months after Trump first threatened to slap import tariffs on steel and aluminum from the region (and beyond). Since then, Trump and the nations he has threatened with tariffs have engaged in a war of words, announcing tit-for-tat import duties on a much wider range of goods.

Trump sees tariffs as a way to protect U.S. jobs and industry and says countries and trading blocs like China and the European Union (EU) are engaged in unfair trade practices, deepening the U.S. trade deficit, when imports exceed exports. In 2017 the U.S.’ trade deficit in goods and services increased 12.1 percent from the previous year, to $566 billion, the Commerce Department reported.

In June, Trump threatened to impose a 20 percent tariff on EU car imports. On Sunday, the Financial Times reported that the EU is prepared to impose retaliatory tariffs worth as much as $300 billion if the U.S. went ahead with such a move.

The BDI’s Lang told CNBC’s Willem Marx that Europe was right to be prepared, but both sides should come back to the negotiating table.

“They (Europe) need to be well prepared because until November and the mid-term elections the U.S. president can do whatever he wants because Congress seems to be very quiet and focused on the elections. And we all need to be prepared for additional tariffs, so it’s important to show some counter-measures,” he said.

“From a business perspective, everyone has to return to the table and discuss how we can reduce tariffs instead of creating new ones… Tariffs in general, whether on steel or aluminum or cars are not a good idea.”