Seventy-six national security experts urged President-elect Donald J. Trump on Monday to reverse his hostility to the nuclear agreement signed with Iran last year and to use it as a tool to ease other tensions with the country.

A report signed by the experts, including former officials from both major political parties, argued that the nuclear agreement had reduced the threat of war in the Middle East.

Mr. Trump has called the nuclear agreement a foreign-policy disaster. He vowed during his campaign to renegotiate or renounce the deal, one of President Obama’s signature achievements.

The report stated, “The deal proved that diplomacy with Iran can bear fruit despite skepticism about Iranian sincerity, the inclination of Iran’s supreme leader to abide by the deal, or the ability of Iranian hard-liners to sabotage diplomacy.”

It urged the incoming Trump administration to use the nuclear agreement as the basis for cooperation on other issues, including a desire by Iran and the United States to eliminate the Islamic State, which has convulsed the Middle East and carried out attacks in the West.

The report was produced by the National Iranian American Council, a Washington group that has advocated improved relations with Iran, even while sharply criticizing Iranian leaders over human rights issues.

“Trump may have been critical of the Iran deal during the campaign, but he will need the deal to remain intact to achieve his other stated goals,” Trita Parsi, the president of the council, said in a statement.

Andrew J. Bacevich, a professor of international relations and history at Boston University who endorsed the report, said the question over whether Mr. Trump “seeks to sustain and broaden the opening to Iran, or distances himself from this opportunity, promises to reveal much about his approach to statecraft.”

Read Rick Gladstone’s full article at the New York Times.