The Trump administration is now trying to derail a German-Russian project to double the capacity of the underwater Nord Stream gas pipeline.
German Chancellor Angela Merkel made a similarly dismissive response to Trump's statement, saying that her country "can make our independent policies and make independent decisions".
In a startling public outburst, Trump told NATO Secretary-General Jens Stoltenberg that Germany was wrong to support a new $11-billion Baltic Sea pipeline to import Russian gas while being slow to meet targets for contributing to NATO defence spending that was meant to protect Europe from Russia.
"Every time I've met with our allies in Europe I've raised those same concerns about Nord Stream II", the name of the pipeline, Ryan said.
In March, Germany agreed to allow Russia's energy-exporting monopoly Gazprom to build a pipeline through its waters.
Still, Trump is using the 4-percent-argument to ram home his message that the US gets a bad deal from allies.
The U.S. president has lambasted U.S. allies for routinely failing to meet a 2 percent goal, a much lower standard that their nations agreed upon before he took office.
During a working breakfast that marked the start of the summit, Trump claimed Germany is "controlled" by Russian Federation due to an energy partnership between the two countries. While Germany's spending is increasing, it will not reach the target by 2024, instead expecting to boost spending to 1.5 percent by 2025.
Perhaps that's why, despite his outbursts, Mr. Trump did not stand in the way of NATO's adoption at the summit of new plans to defend against Russian Federation and terrorism.
Many are using some of those funds for missions in Iraq and Afghanistan that are of critical import to the United States.
In 2018, the USA defense budget is $706 billion.
"The strength of North Atlantic Treaty Organisation is that despite these differences, we have always been able to unite around our core task: to protect and defend each other, because we understand that we are stronger together than apart", Stoltenberg said. The House is expected to cast a similar, non-binding vote on Wednesday.
She recalled her own youth in Soviet-dominated East Germany and said she was "very happy that today we are united in freedom, the Federal Republic of Germany".