Mr Tusk recalled that the Europeans are spending more than Russian Federation and as much as China on defence.
In 2014, before Trump was president, North Atlantic Treaty Organisation members agreed to stop cutting their military budgets and set a goal of moving "toward" spending 2 percent of their gross domestic product on their own defense - by 2024.
Hodges said Europe needed more German trains than German tanks because the capability of transporting the armed forces was vital at present.
As with many Trump crusades, there's truth to his claims-but more to the story.
He will then head to Helsinki for talks with Russian leader Vladimir Putin and some experts have expressed fears the pair will agree the U.S. should station fewer troops in Europe. ("It's not us", Putin has told Trump, according to an American source, summarizing his message, "it's the subordinates fighting against our friendship.") Trump has also reportedly expressed to Putin his desire for better relations, and called the advisers who tried to prevent him from congratulating the strongman on his reelection "stupid people".
"In the actions we take, we are hoping to spur a multilateral response to address some of the world's toughest challenges", Mitchell said. "Will they reimburse the US?"
Speaking with a gaggle of reporters as he left the White House on Tuesday, Trump was asked if he considered Putin a friend or foe.
"It came as shock".
Before he left Andrews Air Force Base, President Trump reiterated his demand for the United States to pay less and other members of the Western military alliance to pay more, and he linked the issue to the EU's trade surplus with the US. "We are stuck without USA leadership".More news: X Games star Travis Pastrana will attempt 3 Evel Knievel jumps
The president touted that the USA lost $151 billion a year ago on trade and slapped tariffs on other countries in an effort towards free and fair trade.
Tusk's pointed observation, offered as he signed a joint declaration with NATO Secretary General Jens Stoltenberg, is unlikely to be the only rhetorical salvo fired this week.
European Union officials say Trump appears uninterested in solutions, however. "Charge us big Tariffs (& Barriers)!"
On defense, Europe and Canada have tried to show they are responding to Trump's demands. Not fair to the USA taxpayer.
He said this summit could be his "easiest" meeting.
"Well, we do have a lot of allies".
"What's new is that this time, it's the president saying it and saying it very bluntly", Bromund said.
Trump's May 8 decision to pull out of Iran accord was a severe setback that has led to talk among EU officials of an "existential moment" in European diplomacy.
On Ukraine: NATO members believe Ukraine is a sovereign nation that should have the ability to rule itself and have its own government, Hutchison said.
That leaves the European Union seeking other alliances, including closer ties with Japan and help from Moscow and Beijing to keep money connected to the nuclear deal flowing to Tehran. "It is always worth knowing who is your strategic friend, and who is your strategic problem", Tusk says.