U.S. Defense Chief James Mattis delivered an ultimatum to NATO countries on Wednesday—either they increase their military spending, or the United States will “moderate its commitment” to the alliance.

“America will meet its responsibilities, but if your nations do not want to see America moderate its commitment to the alliance, each of your capitals needs to show its support for our common defense,” Mattis said.

“No longer can the American taxpayer carry a disproportionate share of the defense of western values,” Mattis added. “Americans cannot care more for your children’s security than you do. Disregard for military readiness demonstrates a lack of respect for ourselves, for the alliance, and for the freedoms we inherited, which are now clearly threatened.”

The comments were made during the first close-doored meeting with NATO defense ministers in Brussels since Trump took office, and were provided to reporters traveling with the new Pentagon chief, RT reported.

These are words that have echoed throughout Trump’s fiery campaign, coming from those who constantly criticized NATO countries along the trail for “not paying their fair share.”

Trump even went as far as to call NATO “obsolete” and said that “NATO doesn’t discuss terrorism, NATO’s not meant for terrorism. NATO doesn’t have the right countries in it for terrorism,” in March. Mattis disagreed and called the idea “kooky” that NATO was obsolete. He called NATO the “fundamental bedrock” and praised NATO, calling it “the most successful military alliance in history.”

Trump echoed a similar sentiment last week when he told troops at MacDill Air Force Base that “the alliance member states must contribute their fair share.”

“We’ll make a historical financial investment in the armed forces of the United States and show the entire world that America stands with those who stand in defense of freedom. We have your back every hour, every day. Now and always. That also means getting our allies to pay their fair share. It’s been very unfair to us. We strongly support NATO. We only ask that all of the NATO members make their full and proper financial contributions to the NATO alliance, which many of them have not been doing. Many of them have not been even close. And they have to do that,” Trump said.

In July of last year, Trump told the New York Times, “You can’t forget the bills, they have an obligation to make payments. Many NATO nations are not making payments, are not making what they’re supposed to make. That’s a big thing. You can’t say forget that.”

However, the 2 percent increase is not a number made up by the Trump administration. In fact, its origin is the Obama administration and NATO Secretary General Jens Stoltenberg who set up the number for major alliance members France, Germany, Italy, Turkey, and Canada, who have not been paying their “fair share.” While countries like UK, Estonia, Poland, and Greece have met the 2 percent margin.

“The main topic I raise in all capitals always is the importance of delivering on the defense investment pledge we made to stop the cuts in defense budgets and to start, gradually to increase and to aim at 2 percent,” Stoltenberg said.

Although, Trump has clarified that he doesn’t want to shrink the United States’s role in NATO as many have erroneously reported; he just wants the nation to pay less, he later told CNN in March.

He also said in July that if Russia attacked one of the countries, he would decide whether to come to their aid only after reviewing if those nations have “fulfilled their obligations to us,” Trump told the New York Times.