BERLIN - President of the German Engineering Federation (VDMA), the country's engineering trade body, on Monday strongly criticized the protective trade policies of US President Donald Trump.

Speaking at the Hanover Trade Fair, VDMA president Carl Martin Welcker expressed "great concern" over Washington's recent announcement of new tariffs on imports. "The biggest risk for industry these days is growing nationalism and protectionism," a statement by Welcker read.

The VDMA president said measures adopted under Trump's "America First" doctrine could not be justified under existing World Trade Organization (WTO) regulations and would undermine the stability of the Geneva-based institution.

He warned the United States against turning its back on the WTO, which provides the foundation for international rules-based trade.

Referring to the US president's widely-publicized habit of sending erratic and often threatening messages online through social media platforms, Welcker argued "the right place to settle trade disputes is the WTO, not Twitter".

The United States is the single largest export market for the German engineering industry, accounting for total annual revenue of 18 billion euros ($22 billion) in 2017.

The VDMA president emphasized, "No one has an interest in the escalation of trade conflicts. At the end of the day, all parties involved, including major economies like the United States, China and the European Union (EU), would lose as a consequence of protectionism."

Welcker urged Trump to reverse his course and re-launch negotiations over the failed Transatlantic Trade and Investment Partnership (TTIP) with the EU.

Earlier, German Chancellor Angela Merkel and Mexican President Pena Nieto both made passionate pledges for free trade during opening speeches at the Hanover Fair.

Hanover Fair, the world's leading industrial trade show, opened on Sunday, as German Chancellor Angela Merkel stressed the importance of free trade.

Speaking at the opening of the fair, Merkel said that multilateral cooperation can add value for everyone. "That's why we are promoting global trade that is as free as possible," she said.

The annual trade fair welcomes visitors from April 23 to 27 and will showcase breaking-edge technologies in artificial intelligence (AI), e-mobility, as well as automated and digitalized manufacturing process (industry 4.0) presented by over 5,000 exhibitors from 75 countries and regions this year.

Hanover fair started in 1947 to boost the economic recovery of post-war Germany. It has repeated every year ever since and become the show window for the world's leading industrial technologies and equipments.