Merkel wondered about Trump's allegations that Russia was "fully controlled" at its annual press conference on Friday.
She told reporters that she wanted to "make an example" to the president.  The Chancellor said, "I try to pay more attention to my language, to be precise, to make sure the facts are true."
"By setting an example, I try this process of brutalization a little bit
She Was Asked for a "Change in Political Culture" Trump's Rhetoric
The leader replied, "I think there is a pretty close connection between thinking, speaking and acting."  Trump has repeatedly attacked the German leader in recent months, most recently last week.
The president accused Germany of being "completely controlled" at a NATO summit in Russia.
In his televised statements broadcast worldwide, he said Trump: "I find it very sad when Germany makes a massive oil and gas deal with Russia, where they should guard against Russia and Germany runs out and billions and billions D a year to Russia.
He continued to criticize Merkel's French neighbors and added: "So we protect Germany, we are pr. We protect all these countries. And then many of the countries go out and make a pipeline deal with Russia, where they pay billions of dollars into the coffers of Russia.
"I think that's very inappropriate."
Ms. Merkel stayed calm on Friday
adding she had not tried to "investigate the causes of Trump's behavior."
Despite the differences, Merkel described Trump as an "important partner"
She added: "We see the US as an important partner."
"A partner who does not always follow the policy we agree with, but it is worth to lead these conflicts. "