When it was her turn to address reporters in the room for the meeting with Trump, Merkel made no similar declaration about her relationship with Trump.
Germany is extremely reliant on Russian gas, and the new Nord Stream 2 pipeline in the Baltic Sea, which Germany approved in March, will only increase its dependence. The pipeline is opposed by the U.S. and some EU members, including European Council President Donald Tusk.
With Trump's much-anticipated summit with Putin just five days away, Stoltenberg appeared to get in a shot of his own, telling Trump other North Atlantic Treaty Organisation leaders are "looking forward to your thoughts about the meeting with President Putin later on".
Stoltenberg estimated European allies and Canada will add $266 billion to their military spending by 2024 and said "this is really adding some extra momentum", apparently meaning Trump's pressure.
And with that, he went on to push allies at the summit to double their commitment on defence spending.
Trump also misrepresented Germany's energy picture, asserting coal and nuclear power are gone from the mix.
"President Trump's brazen insults and denigration of one of America's most steadfast allies, Germany, is an embarrassment", they wrote.
TRUMP: "Frankly, many countries owe us a tremendous amount of money for many years back, where they're delinquent, as far as I'm concerned, because the United States has had to pay for them". Germans wouldn't agree with that.
"We do have disagreements, but most importantly, we have decisions that are pushing this alliance forward and making us stronger", Stoltenberg said.
In March, Germany agreed to allow Russia's energy-exporting monopoly Gazprom to build a pipeline through its waters.
"The point she's making is that you can see the list of activities she points to, the way Russian Federation are behaving, and she's saying firstly that it's important that there's a price to pay for this, and we work together as allies to make sure that's enforced".
Before an evening program, Trump met with Germany's Angela Merkel and France's Emmanuel Macron. "That is very good, especially for people in eastern Germany".
Trump asked. "When we stand together, also in dealing with Russian Federation, we are stronger", Stoltenberg replied.
Currently, NATO members are encouraged to put a target of 2% of their economic output to the Organization's budget, but the 2% figure is only a guideline. Sitting at the table with the president were Secretary of Defense James Mattis, Chief of Staff John Kelly, Secretary of State Mike Pompeo and NATO Ambassador Kay Bailey Hutchison, Trump defended his public reprimanding of allied countries over their defense spending. "We are supposed to be guarding against Russia and Germany goes out and pays billions and billions dollars a year to Russia", Mr Trump said.
Numerous issues are not new; former President Barack Obama, who enjoyed a close relationship with Merkel, was critical of the German export surplus, its defense spending and the Nord Stream 2 pipeline project with Russian Federation.