Updated at 11:22 a.m. ET.

President Trump defended his "America First" agenda in a speech to the United Nations General Assembly on Tuesday, in effect spiking the football at what his secretary of state described as the "Super Bowl of diplomacy."

"The United States is a stronger, safer and richer country than it was when I assumed office less than two years ago," Trump declared. "We are standing up for America and the American people, and we are also standing up for the world."

Trump has withdrawn the U.S. from the Iran nuclear deal, the Paris climate accord and an Asia-Pacific trade pact, while imposing steep tariffs on both allies and adversaries. He insisted his focus on American "sovereignty" has paid off, helping to foster both peace and prosperity.

Tensions with North Korea have eased since last year's General Assembly, when Trump called North Korean leader Kim Jong Un "rocket man" and threatened to "totally destroy" the country if it threatened the U.S. or its allies.

On Tuesday, Trump touted "tremendous progress" in his negotiations with Kim, even though the North Korean leader has so far taken few concrete steps to eliminate his country's illicit nuclear program.

Although the president's approach to North Korea has softened in the past year, his attitude toward Iran has not.

"Iran's leaders sow chaos, death and destruction," Trump said. "They do not respect their neighbors or borders or the sovereign rights of nations."

Since withdrawing from the Iran nuclear deal, the U.S. has reimposed sanctions on the regime, and Trump is urging reluctant partners to do the same.

"The United States has launched a campaign of economic pressure to deny the regime the funds it needs to advance its bloody agenda," he said. Other parties to the nuclear deal are reluctant to go along, noting that Iran continues to abide by the terms of the agreement.

Iran's behavior will also be a major focus Wednesday when Trump leads a meeting of the U.N. Security Council. Secretary of State Mike Pompeo said the U.S. considers Iran the leading state sponsor of terrorism.

Trump defended his aggressive use of tariffs, against not only China but also close allies like Canada and the European Union.

"We believe that trade must be fair and reciprocal," Trump said. "We will not allow our workers to be victimized, our companies to be cheated, and our wealth to be plundered and transferred."

The international community has reacted warily to the president who seems determined to unwind the world order that his predecessors spent decades building and who isn't shy about blowing his own horn.

"In less than two years, my administration has accomplished more than almost any administration in the history of our country," Trump said, prompting laughter in the U.N. hall.

"I didn't expect that reaction," Trump said. "But that's OK."

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