Waltz Warns Iran Sanctions Evaders, Touts Greenland Deal

President Donald Trump is heading back to the United Nations this week, urging countries to work more closely with Washington against Iran while his administration pursues sweeping changes to the international body, U.S. Ambassador to the U.N. Mike Waltz told News Outlet in an exclusive interview before the summit.

US presses allies to enforce Iran sanctions ahead of the UN General Assembly

As the U.S.-Iran war approaches its seventh month, Trump is scheduled to speak to the General Assembly on Tuesday and sit down with Gulf leaders whose nations have been directly impacted by the conflict.

The high-level meeting comes as the White House prepares to tighten financial pressure on Tehran, European partners continue responding to Russia’s war in Ukraine, and critics question whether plans to shrink the U.N. and cut its budget could weaken its ability to manage global emergencies.

Waltz said Washington expects its allies and partners to fully enforce sanctions against Iran, warning that nations that ignore the measures could face penalties.

“They will reinforce that message, but importantly, it’s all of these countries actually enforcing the sanctions and what they’re going to hear is there will be consequences for friend and foe,” Waltz said. “The president is doing this for the future security of the world.”

Many European and Asian allies have so far resisted Trump’s appeals for help in the Iran conflict, which began after U.S. and Israeli strikes in February, Reuters reported Sept. 18. The fighting has also unsettled global energy markets, as Iran has interfered with shipping in the Strait of Hormuz and its Houthi allies have strengthened their control over a key Red Sea trade route.

According to Waltz, enforcing the sanctions will be a major focus of the Trump administration’s diplomatic efforts during the United Nations General Assembly.

“The Iranian economy continues to crater,” Waltz said, citing the country’s weakened currency, rising inflation and the U.S. naval blockade. He added that Trump has been unequivocal about the administration’s objective: “Iran cannot and will not have a nuclear weapon.”

The ambassador spoke days after Russia and China used their veto power at the Sept. 17 U.N. Security Council meeting to block a proposal extending independent oversight of international sanctions on Iran.

Trump is also expected to confer with Gulf leaders about the war and wider regional security. Waltz said the administration hopes to hear firsthand about the concerns of its Gulf partners, calling the joint meeting a valuable moment for diplomacy.

JEFF BARTOS SAYS UN REFORM IS NO LONGER AN ‘OXYMORON’ AFTER $570M IN CUTS

A UN the Trump administration wants to change — but not abandon

The conflict with Iran is unfolding alongside a larger argument over the U.N.’s future. Trump has repeatedly criticized the organization, while his administration has advanced plans for major structural and financial reforms.

The United States paid $725 million toward the U.N.’s regular budget on Sept. 16, along with $102 million for peacekeeping. The payments lowered Washington’s arrears and temporarily avoided the possibility of losing its General Assembly voting rights in 2027. Even so, the U.S. continued to owe about $1.312 billion to the regular budget, U.N. figures showed.

When asked why American taxpayers should keep supporting an institution the administration has accused of anti-American bias, Waltz highlighted efforts to reduce expenses and refocus the U.N. on what he described as its core responsibilities.

“The president is clear about getting the U.N. back to basics and helping it realize its potential,” Waltz told News Outlet.

Waltz said the administration had achieved more than $1 billion in budget cuts, including the elimination of roughly 3,000 headquarters jobs and an estimated 25% reduction in peacekeeping personnel.

“We have the U.N. on a diet,” Waltz said.

But Waltz also made clear that the administration does not intend to abandon the United Nations.

“There’s got to be one place in the world where everyone can come together and put diplomacy first and can actually talk,” he said. “We don’t ever want to see a U.N. in Beijing or Moscow or Brussels.”

“If we just walked away, you’d have 192 countries talking without us,” Waltz added.

Gaza offers one example of how the administration intends to use the U.N. while limiting direct American military involvement. Waltz pointed to the U.N.-endorsed Board of Peace and the planned International Stabilization Force, which is intended to support security and a postwar transition in Gaza. The ambassador said he does not want American troops deployed there, arguing that international security operations should allow other countries to share the burden. The U.N. Security Council endorsed the Gaza peace plan and authorized the stabilization force in November 2025.

The State Department said Sept. 18 that Secretary of State Marco Rubio will be in New York from Sept. 20–23 to meet foreign counterparts, advance U.S. security and economic priorities and continue the administration’s campaign for U.N. reform.

Greenland agreement adds another dimension to allied diplomacy

Trump arrives in New York days after announcing a new security agreement with Denmark and Greenland aimed at expanding the American military presence in the Arctic while restricting adversaries from establishing bases or making sensitive investments on the island.

The agreement falls short of Trump’s earlier ambition to acquire Greenland, which remains an autonomous territory within the Kingdom of Denmark. Denmark and Greenland have stressed that the arrangement will not compromise the island’s sovereignty or right to self-determination. Additional details of the agreement have yet to be made public.

Waltz told News Outlet that the deal reflects the Arctic’s growing strategic importance as melting ice opens new shipping routes and increases access to energy and mineral resources.

“It’s incredibly significant,” Waltz said, pointing to Russia’s Arctic military capabilities and the potential for new shipping routes to transform global trade.

“It took some tough tweets, maybe some tough language,” he said. “We now have an agreement with our ally Denmark.”

The agreement comes as European governments confront overlapping security challenges involving Russia’s war in Ukraine, Arctic defense and uncertainty over transatlantic security arrangements, while Washington seeks greater allied cooperation in its campaign against Iran.

World leaders converge on New York

The U.N. expects 73 heads of state and 45 heads of government, along with 49 ministers, 11 vice presidents and one crown prince, to attend High-Level Week, U.N. spokesperson Stéphane Dujarric told reporters Friday.

Member states have submitted approximately 1,000 requests for bilateral meetings, while about 168 events are scheduled alongside the official proceedings.

The 81st General Assembly’s General Debate begins Tuesday and runs through Sept. 28.

Beyond Iran, world leaders are expected to address Russia’s invasion of Ukraine, the future of Gaza, international security and the U.N.’s ability to respond to emerging global challenges.

Waltz described the administration’s approach with a slogan inspired by the president’s political branding: “Make the U.N. great again.”

But the immediate diplomatic questions facing Washington are more concrete: whether allies will increase pressure on Iran, whether Gulf leaders can agree on a path toward ending the conflict and whether the administration’s push for a leaner U.N. can coexist with its efforts to use the organization to address international security challenges.