A year ago, European Commission President Ursula von der Leyen and US President Donald Trump struck a trade deal in Turnberry, Scotland, shaking hands under the spotlight of the world's media after weeks of trade disputes.

Defended by the Commission as the best deal it could secure, the agreement imposed 15 percent US tariffs on imports from the EU, while the EU committed to removing its duties on most US industrial products.

The Europeans also pledged to invest €520 billion in the US and purchase €700 billion in US energy by 2028, including liquefied natural gas (LNG), oil and nuclear energy products.

The Turnberry agreement was supposed to draw a line under the dispute. Instead, it opened a new chapter.

Over the past year, Trump has repeatedly threatened the EU with new tariffs, slowing the implementation of the agreement on the European side, where lawmakers froze its ratification. Following negotiations between the EU's co-legislators, the bloc eventually removed its tariffs on 1 July.