WASHINGTON — When President Trump welcomes Chancellor Angela Merkel of Germany to the Oval Office on Tuesday, their meeting will take on a symbolism unlike any he has held so far: The great disrupter confronts the last defender of the liberal world order.

Mr. Trump and Ms. Merkel are poles apart on issues like immigration and trade; they have circled each other warily since the American presidential election. But both sides, officials said, are determined not to let this first meeting devolve into a clash of competing worldviews.

Ms. Merkel has been studying Mr. Trump’s speeches to get an insight into the new president’s thinking. American officials said Mr. Trump would ask the chancellor for advice on how to deal with President Vladimir V. Putin of Russia, whom, after dozens of meetings over her 11 years in power, she knows better than any other leader in the West.

The threat posed by Russia to Europe could give Ms. Merkel and Mr. Trump a sliver of common ground. The Trump administration is demanding that Germany and its other NATO allies increase their military budgets, a message the Germans appear to be taking to heart, even if their spending still falls well short of what the United States would like.