As European Commission President Ursula von der Leyen is set to meet with President Donald Trump this weekend to discuss trade, Trump himself may be the biggest hurdle standing in the way of a deal.

Investors are hopeful a potential trade deal between the U.S. and European Union could bring more certainty to markets ahead of next Friday's tariffs deadline.

"In a non-deal scenario without another delay of US tariffs, I see the EU going for a tit-for-tat approach, ie imposing 30% tariffs on selected US goods, not yet all goods, like the well-known motorcycles, cars, clothing and alcohol," he said in emailed comments.