Donald Trump, Angela Merkel
From left: US President Donald Trump, German Chancellor Angela Merkel Getty Images

It is hard to imagine two world leaders whose styles and approach more different, but on Tuesday (14 March) Donald Trump will meet Europe's most powerful politician, German Chancellor Angela Merkel.

The meeting between the billionaire real estate mogul and the cautious East German physicist will be watched by nations all over the world in what will be a high-stakes encounter.

Ever since Trump was elected as president in November, the pair have engaged in a series of strongly worded statements.

In an interview in January, Donald Trump said Merkel had made a "catastrophic" mistake in letting tens of thousands of refugees enter Germany.

Trade between the US and Europe is "advantageous for both sides," Merkel said after meeting German business leaders in Munich on Monday.

"Talking directly is always much better than talking about each other," she said. "That will be my motto on this visit, which I am looking forward to."

Merkel will be joined by several leading business CEOs, including the bosses of BMW and Siemens – who collectively employ more than 130,000 Americans.

Now in her twelfth year as chancellor, Trump is Ms Merkel's third US President, following George W Bush and Barack Obama.

The German leader will also be walking a fine line in Washington. With an election looming at home in September, she must avoid offering her political opponents ammunition by cosying up to Trump.

At the same time she cannot afford an open confrontation that might damage German interests.

Expecting the unexpected

One thing which the Merkel camp cannot prepare for are surprises that can come in many forms.

Thee surprises have caused issues for British PM Theresa May, Japanese PM Shinzo Abe and the Israeli Prime Minister Benjamin Netanyahu.

Headlines were made when May was photographed holding hands with Trump as they walked down a flight of steps at the White House.

Abe also had a hand incident, with an awkward 20-second shake causing a stir amongst the press.

And despite rigorous preparation, Benjamin Netanyahu's team were still taken aback when Trump spoke off the cuff at their news conference on the sensitive issues of settlements and a future Palestinian state.