The German minister made the remarks in an interview with Bild am Sonntag
newspaper on Sunday, emphasizing that Berlin would not let the Washington dictate its trade rules on it.
He added that Washington’s sanctions on Iran clearly showed America’s neglect of its partners.
"We won't let Washington dictate us with whom we can do business and we therefore stick to the Vienna Nuclear Agreement," Altmaier said in reference to a landmark nuclear deal between Iran and the P5+1 group of countries in 2015, which is officially known as the Joint Comprehensive Plan of Action (JCPOA).
Under the deal, Iran undertook to put limits on its nuclear program in exchange for the removal of nuclear-related sanctions imposed against Tehran.
Trump pulled the US out of the Iran nuclear agreement in May, and said that he plans to reinstate US nuclear sanctions on Iran and impose "the highest level" of economic bans on the Islamic Republic.
On Monday, Trump signed an executive order reimposing sanctions on Iran to levy "maximum economic pressure" on the Islamic Republic.
Elsewhere in his remarks, the German minister said his country should be more assertive and defy American sanctions particularly by investing more in Iran.
He emphasized that Germany and other European countries should feel free to pursue improved relations with Tehran.
“German businesses can continue to invest as much as they want in Iran,” Altmaier was quoted as saying in a report that was also carried by the website of Russia Today, adding that the German government was looking for ways together with its European allies to ensure that financial transactions could still take place with Iran.
Altmaier’s words came after US President Donald Trump ordered to restore a fresh round of sanctions targeting Iran’s purchase of US dollars.
These restrictions, among other things, are aimed at damaging EU ties with Iran, which had flourished following the conclusion of the nuclear deal.
Last week, the EU reponded to Washington’s sanctions against Iran by calling on companies to disregard threats from the US.
Apart from the issue of Iran, the US and Europe are locked in a dispute over tariffs on steel, aluminum, and automobiles.
With that in mind, the German minister said, the world now risks sliding into an all-out economic conflict, adding that “we are just a few yards from the edge,” and “a global trade war would not know winners, only losers.”
Politicians have no right to jeopardize hundreds of thousands of European jobs that depend on US-EU trade, he emphasized.
“We have learnt from the past that mostly customers are suffering from trade wars as goods and services are getting more expensive,” Altmaier said, adding, “This trade war hampers economic growth and brings new uncertainties.”