Since Donald Trump took office just over a year ago, the string of high-profile white house resignations has been staggering. On Tuesday, Gary Cohn, Trump's top economic adviser, resigned from his post. According to the New York Times, he did so because of his opposition to the president's decision to impose tough trade tariffs.

Commentators believe, Cohn considered quitting last August after Donald Trump's controversial comments on the Charleville race riots.

But it was the decision to introduce tariffs on aluminium and steel imports that reportedly caused an insurmountable rift between Trump and Cohn.

Both Cohn and the treasury secretary, Steven Mnuchin, are said to have strongly opposed the trade tariffs.

Cohn was seen as moderating influence on Trump

During his tenure, Cohn helped to push through many of Donald Trump's economic reforms, including the tax cuts. As a Democrat, many believed him to have had a moderating influence on Trump's economic policies. Once one of Trump's personal favourites, Cohn said in a statement that he had been pleased to work on pro-growth policies and tax reforms.

However, the decision to proceed with the introduction of trade tariffs appears to have been a step too far for Cohn.

In a statement to the New York Times, Donald Trump praised Cohn's contribution:"He's a rare talent, and I thank him for his dedicated service to the American people." On Tuesday, he took to Twitter to ponder who'd be a possible successor.

President Trump's trade tariffs

It's not just Gary Cohn and Steven Mnuchin who've been critical of Trump's decision to impose trade tariffs. Many Republicans have been equally scathing, fearing that tariffs could spark an international trade war.

Stock markets have also reacted to Donald Trump's decision, and some believe, Cohn's resignation could rattle them further.

Nonetheless, Donald Trump seems determined to push ahead with the introduction of tariffs on steel and aluminium, reiterating, that the US was on the losing side of many trade deals.

Trump highly critical of the European Union

At a press conference with the Swedish prime minister, Trump said that it was near impossible to do business with the European Union. He went on to say that the EU "has been particularly tough on the United States", and that "the European Union has not treated us well and it's been a very, very unfair trade situation."

Previously, Donald Trump had criticised the German car industry, sentiments he reiterated on Saturday on Twitter.

European Union response

Responding to Donald Trump's trade tariff announcement, the European Union announced it would ask Washington for a rethink.

However, if the US were to go ahead with the introduction of a 10 percent tariff on aluminium and 25 percent on steel, the European Union believes many European jobs would be at risk. For that reason, the European Union would see itself forced to take action. First, the EU would seek support from the World Trade organisation to oppose the US tariffs. Secondly, it would introduce measures to protect the openness of the European market. Finally, the EU would look at rebalancing the losses resulting from the imposition of the US tariffs by placing tariffs on certain US products. The European Union stressed that all measures would comply with WTO regulations.