Pelosi {link:tweeted: "https://twitter.com/SpeakerPelosi/status/1113470601753133056?s=20"}, "For 70 years, America’s relationships with our @NATO allies have formed the foundation of our efforts to make the world a more secure & peaceful place. As we mark this historic anniversary, we affirm America’s ironclad commitment to NATO & achieving permanent peace." Photo by Kevin Dietsch/UPI

Stoltenberg visited President Donald Trump at the White House on Tuesday. Trump has threatened to withdraw the United States from NATO, saying some of the other countries aren't paying their fair share on defense and instead lean too heavily on the U.S. military. The United States spends 3.5 percent of its GDP on defense, the most of any NATO ally. Photo by Kevin Dietsch/UPI

On NATO's 70th anniversary Thursday, foreign ministers of NATO's 29 member nations will meet officials at the State Department -- partly to discuss Russia. They're expected to endorse a set of measures in the Black Sea to improve NATO's defenses in the region. Photo by Kevin Dietsch/UPI

Stoltenberg is the first NATO secretary-general to address a joint meeting of Congress in the United States, accepting an invitation extended last month by Pelosi and Senate Republican Leader Mitch McConnell -- intended to show bipartisan support for the 70-year-old alliance. Photo by Kevin Dietsch/UPI

NATO Secretary-General Jens Stoltenberg addresses a joint session of Congress at the Capitol with Vice President Mike Pence (L) and Speaker of the House Nancy Pelosi, D-Calif., seated behind him. Photo by Kevin Dietsch/UPI

April 3 (UPI) -- In the first-ever address by a NATO leader to a joint session of U.S. Congress, Secretary-General Jens Stoltenberg said Wednesday the security role filled by the 70-year-old European alliance is critical in preserving peace.

NATO was formed in 1949 by 12 countries to form a strong union and guard each other against a growing communist threat from the Soviet Union and other potential enemies. Stoltenberg said in his speech Wednesday NATO still provides that security for 29 member nations -- and Russia is still one of the chief threats.


"Ever since the founding of NATO in 1949, every Congress, every American president, your men and women in uniform, and the people of the United States of America, have been staunch supporters of NATO," he said. "America has been the backbone of our alliance.

"Through NATO, the United States has more friends and allies than any other power."

His remarks came a day after he met with President Donald Trump at the White House. Trump has repeatedly criticized NATO since taking office in 2017 and slammed member nations who've not met defense spending obligations. The alliance asks that each member spend 2 percent of its gross domestic product on its own defense. Trump made it clear at a NATO summit in Belgium last summer the spending guideline should be doubled to 4 percent by 2025.

"Questions are being asked on both sides of the Atlantic about the strength of our partnership," Stoltenberg said Wednesday. "We have overcome our disagreements in the past. And we must overcome our differences now. Because we will need our Alliance even more in the future."

Trump told Stoltenberg at the White House Tuesday the 2 percent figure "may have to go up," and Stoltenberg has said Canadian and European allies have already agreed to increase their spending. In February, Stoltenberg said 15 of the 29 NATO allies were projected to meet their goal and all members have increased spending.

"Together, we represent almost one billion people," he said. "We are half of the world's economic might. And half of the world's military might.

"When we stand together, we are stronger than any potential challenger -- economically, politically and militarily."

Stoltenberg is the first NATO secretary-general to address a joint meeting of U.S. Congress. He accepted an invitation last month by House Speaker Nancy Pelosi and Senate Republican leader Mitch McConnell -- as a show of bipartisan support for NATO. McConnell's office told UPI the speech would give Stoltenberg an opportunity to address the concerns floated by Trump.

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On NATO's 70th anniversary Thursday, foreign ministers of the 29 member nations will meet U.S. officials at the State Department -- partly to discuss Russia. They're expected to endorse a set of measures in the Black Sea to improve NATO's defenses in the region.

Prior to arriving in Washington, Stoltenberg said, "The strength of NATO is that, despite these differences, we have always been able to unite around our core tasks.

"That is, to protect and defend each other."

A Gallup poll last month showed 77 percent of Americans believe NATO should be maintained. The House voted 357-22 in January to pass a bill to prevent Trump from withdrawing the United States from NATO, which the president has hinted at in the past.