U.S. Ambassador to the U.N. Nikki Haley speaks during a news briefing at the White House in Washington on Sept. 15. (Carolyn Kaster/AP)

As world leaders converge on New York this week for the U.N. General Assembly, a U.N. body is set to publicly call for the release of two Iranian Americans imprisoned unjustly in Tehran. That creates an opportunity for the Trump administration to make good on its promise to ramp up efforts to bring American hostages home.

With Iranian President Hassan Rouhani and Foreign Minister Mohammad Javad Zarif present with him in New York, President Trump is expected to focus on the future of the Iran nuclear deal, Iranian military expansion in the Middle East and the regime’s human rights abuses. But the subject of American hostages is also a stated priority of the Trump White House. The question is whether the president will give it equal billing or put the fate of the U.S. prisoners on a back burner.

The U.N. Working Group on Arbitrary Detention, a body created by the U.N. Human Rights Council, has issued an official opinion stating Iran is unjustly imprisoning two Iranian Americans, Baquer and Siamak Namazi, in violation of the Universal Declaration of Human Rights and the International Covenant on Civil and Political Rights. The judgment is being released Monday.

“The Working Group considers that . . . the appropriate remedy would be to release [them] immediately and accord them an enforceable right to compensation and other reparations,” the opinion states.

Both Namazis were sentenced this past October to 10 years in Iran’s notorious Evin prison after show trials for the charge of “collusion with an enemy state,” referring to the United States. Behind the scenes, the White House has been working with Babak Namazi, Baquer’s son and Siamak’s brother, to press for their release.

Babak Namazi told me in an interview that Rouhani and Zarif should not be allowed to visit the United Nations without being confronted about the imprisonment of his family members.

“The international community and the U.S. have to press upon them that taking hostages is a great injustice,” he said. “I hope member states take this ruling as further evidence that Iran is in violation of international law and press them to release them, before it’s too late.”

Baquer Namazi is 81 and in poor health. He served for more than a decade as a senior official at UNICEF, which is also involved in advocating his release. Babak Namazi has met with senior Trump administration officials, including U.S. Ambassador to the U.N. Nikki Haley and deputy national security adviser Dina Powell.

In July, after Iran handed down a 10-year sentence for Chinese American graduate student Xiyue Wang, the White House issued a statement announcing that the administration was "redoubling efforts" to secure the release of Americans held hostage in Iran, including the Namazis and former FBI official Robert Levinson, who has been missing for more than a decade.

“President Trump is prepared to impose new and serious consequences on Iran unless all unjustly imprisoned American citizens are released and returned,” the statement read.

Administration officials said punitive measures on Iran related to the hostages were being considered as part of the administration's overall Iran policy review, which is reportedly near completion. That policy could be rolled out next month, when the White House is also required to announce the way forward for the nuclear deal.

In the meantime, Trump and his senior national security aides could do several things to bring the issue of Iranian hostage-taking to the fore. First, Trump could mention the issue in his first-ever address to the U.N. General Assembly on Tuesday. Next, the administration could announce new human-rights-related sanctions designations, which are not prohibited under the nuclear deal.

The Trump administration could also use its meetings with allies in New York to work on a broader prisoner swap to bring the Americans home. When Zarif visited the United States in July, he complained that the administration had orchestrated the arrest of several Iranians here and in several other countries and called for their release "from a humanitarian perspective."

In January 2016, the Obama administration struck a prisoner deal with Iran that resulted in the release of four Americans, but Siamak Namazi was not among them. Zarif reportedly promised to secure his release but then failed to deliver.

In previewing the administration’s participation in this week’s General Assembly, Haley touted a renewed U.S. commitment to making the United Nations more relevant and more geared toward confronting and solving real problems.

The United Nations is now "not just about talking, it's about action," she said.

Confronting Iranian leaders about American prisoners while the leaders are on American soil this week could show there is something behind that claim.

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