Saudi Crown Prince Mohammed bin Salman meets with Defense Secretary Jim Mattis at the Pentagon in Washington on Thursday, March 22, 2018. (Cliff Owen/AP)

Saudi Crown Prince Mohammed bin Salman said Thursday it would be “really insane” for him to trade classified information with presidential son-in-law and White House adviser Jared Kushner, or to try to use Kushner to promote Saudi aims within the Trump administration.

That kind of relationship “will not help us” and does not exist, he said. Speaking in a meeting with Washington Post editors and reporters, Mohammed denied U.S. media reports that he had claimed Kushner was “in his pocket,” or that, when the two met in Riyadh in October, he had sought or received a green light from Kushner for massive arrests of allegedly corrupt members of the royal family and Saudi businessmen that took place in the kingdom shortly afterward.

The detentions were solely a domestic issue and had been in the works for years, the prince said.

While “we work together as friends, more than partners,” Mohammed said, his relationship with Kushner was within the normal context of government-to-government contacts. He noted that he also had good relations with Vice President Pence and others in the White House.

In the 75-minute meeting at The Post on the last day of his four-day stay in Washington, Mohammed was animated and engaged, fielding questions on a range of topics, from the war in Yemen to the Middle East peace process, Iran, his domestic reform agenda, human rights and Saudi Arabia’s nuclear plans.

Although the meeting, conducted in English, was held off the record, the Saudi Embassy later agreed that specified portions could be used in an article about the session.

The son of King Salman and heir to the Saudi throne, Mohammed, 32, met with President Trump on Tuesday in the Oval Office and over lunch. He also spoke with a number of congressional leaders — many of whom have been critical of the U.S.-aided Saudi war in Yemen. On Thursday, he visited Defense Secretary Jim Mattis at the Pentagon. The crown prince also serves as Saudi Arabia’s defense minister.

But the centerpiece of his nearly three-week tour of the United States will come in subsequent stops in Boston, New York, Seattle, Silicon Valley, Los Angeles and Houston.

Even as Trump has said he is seeking increased investment and purchases of U.S. military equipment and other products from Saudi Arabia, Mohammed has made clear that his primary mission here is to win U.S. investor confidence in his country, along with technological and education assistance in his efforts to reform the ultraconservative kingdom.

China and Russia are vying with the United States to build components of new nuclear power plants in the kingdom, amid concerns here over a Saudi desire for uranium enrichment capability. In an interview with CBS’s “60 Minutes” broadcast last Sunday, Mohammed said that his country would build a nuclear weapon if Iran did.

At The Post, he said his primary concern was being able to enrich and use Saudi Arabia’s own uranium for use in power reactors, rather than buying it abroad. His country has more than 5 percent of the world’s uranium reserves, and “if we don’t use it, it’s like telling us don’t use oil.” The United States, he said, would be invited to put in place laws and structures to make sure enriched uranium is not misused.

Mohammed spoke at length about the prospects for economic growth in the Middle East, saying it could be “the next Europe” if a series of problems can be resolved.

One of those is the decades-long Israeli-Palestinian dispute. Trump has designated Kushner to come up with a peace plan, and Kushner met here with Mohammed this week, along with Jason Greenblatt, a Trump Organization lawyer brought into the White House to help with the effort.

Once the U.S. plan is ready, Kushner is said to want the Saudis and other leading Arab countries to help persuade the Palestinians to accept it.

The official Saudi position is that any peace agreement must recognize a Palestinian state within specified borders, with East Jerusalem as its capital. Arab leaders have said that Trump’s recent recognition of Jerusalem as Israel’s capital — a move that Mohammed called “painful” — has made a deal under U.S. auspices far more difficult.

On the Yemen war, Mohammed said that Saudi Arabia had not passed up “any opportunity” to improve the humanitarian situation, although human rights organizations and U.S. law­makers have said Saudi bombing has caused many of the more than 5,000 estimated civilian deaths in the war.

“There are not good options and bad options. The options are between bad and worse,” he said of the Yemen conflict with Iran-backed Houthi rebels who overthrew the Saudi-recognized government.

Discussing his reform efforts at home, including giving women the right to drive and have more rights outside the home, Mohammed said he has worked hard to convince conservative religious leaders such restrictions are not part of Islamic doctrine.

“I believe Islam is sensible, Islam is simple, and people are trying to hijack it,” he said. Lengthy discussions with clerics, he said, have been positive and are “why we have more allies in the religious establishment, day by day.”

Asked about the Saudi-funded spread of Wahhabism, the austere faith that is dominant in the kingdom and that some have accused of being a source of global terrorism, Mohammed said that investments in mosques and madrassas overseas were rooted in the Cold War, when allies asked Saudi Arabia to use its resources to prevent inroads in Muslim countries by the Soviet Union.

Successive Saudi governments lost track of the effort, he said, and now “we have to get it all back.” Funding now comes largely from Saudi-based “foundations,” he said, rather than from the government.