"Dear America, appreciate your allies, after all you don't have that many," Tusk said addressing Trump at the signing ceremony of the Joint Declaration on EU-NATO cooperation, stressing that the United States would never find a better ally than Europe.
He also slammed the US president for "criticizing Europe almost daily."
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Earlier in the day, Trump in a tweet heavily criticized the EU's approach to trade ahead of the upcoming summit between the European Union and the North Atlantic Treaty Organization.
Getting ready to leave for Europe. First meeting — NATO. The U.S. is spending many times more than any other country in order to protect them. Not fair to the U.S. taxpayer. On top of that we lose $151 Billion on Trade with the European Union. Charge us big Tariffs (& Barriers)!
— Donald J. Trump (@realDonaldTrump) July 10, 2018
Meanwhile, NATO's Secretary General Jens Stoltenberg said that the alliance's member states made the biggest increase in defense spending in a generation in 2017.
"We’ll release 2018 defence spending estimates for each Ally: last year saw the biggest increase in a generation & this is the 4th consecutive year of real increases + we expect 8 Allies to spend at least 2% of GDP on defence compared to 3 in 2014," Stoltenberg said as quoted by NATO spokeswoman Oana Lungescu.
Stoltenberg also said that since 2014 all the member states have stopped the cuts in defense spending.
The Trump administration has repeatedly pressured European states to inject greater sums in NATO, citing most EU countries' inability to meet the alliance's defense spending target of 2 percent of their GDP, stressing that NATO benefits Europe much more than the United States.