During an important meeting with Japanese Prime Minister Shinzo Abe in February 2017, President Donald Trump asked the leader to consider allowing American casinos to build in his country.

One US casino company Trump essentially lobbied for — Las Vegas Sands — is owned by Sheldon Adelson, the powerful casino mogul and conservative megadonor who contributed at least $20 million to Trump’s presidential campaign. What’s more, Trump had dinner with Adelson the day before meeting with Abe, although it’s unclear if the casino issue came up during that meal.

That’s one of the most shocking tidbits in a story by ProPublica on Wednesday. If true, it shows that Trump stepped wildly out of bounds in two concrete ways.

First, he used a vital meeting with the leader of a close US ally to talk about a private business deal. Those kinds of conversations rarely happen when heads of state meet each other, as the topics typically center around security and bilateral issues.

And second, it’s highly unethical — and abnormal — for a president to help a donor do business in a foreign country, even if Trump also mentioned other casinos as well.

“While there are times that it is appropriate for the president to promote business interests, it must be for the benefit of the American people, not his personal relationships,” says Jordan Libowitz of Citizens for Responsibility and Ethics in Washington, a watchdog group.

“President Trump’s blurring of the line between the administration and his personal interests casts a shadow on of doubt on these activities,” Libowitz adds.

But Trump also blurred the lines on how America deals with one of its top allies.

Japan just legalized casino gambling in July, permitting the construction of only three casino resorts for now. That’s why Adelson’s company, Las Vegas Sands, as well as other American casino companies desperately want one of those limited spots. It’s estimated that the casino industry in Japan could be worth around $25 billion a year.

ProPublica reports that Abe and his team were taken aback by Trump’s comments during their meeting:

“It was totally brought up out of the blue,” according to one of the people briefed on the exchange. “They were a little incredulous that he would be so brazen.” After Trump told Abe he should strongly consider Las Vegas Sands for a license, “Abe didn’t really respond, and said thank you for the information,” this person said.

Sheila Smith, a Japan expert at the Council on Foreign Relations, points out that a US president advocating for American business interests in Japan is nothing new. “President Bush famously took a group of automakers to Japan, and other industries have also been the focus of attention in trade negotiations,” she told me.

But, she added, “it is unusual for a president to represent one company’s interests, especially in a business that is so controversial in Japan.”

Trump acts like America’s top corporate spokesperson

Trump has also pushed a “Buy American” campaign for arms sales. On more than one occasion, he’s used a conversation with a foreign leader to convince them to buy US-made products.

In January, for example, Trump pressed the emir of Kuwait to agree on a $10 billion fighter jet deal that hadn’t moved forward in more than a year. Boeing, the US-based defense and commercial aviation company, had struggled to finalize the agreement. So Trump stepped in to make it happen, an unusual move for an American president.

And according to Reuters, Trump has authorized members of his Cabinet to act like “closers” on major weapons deals.

It perhaps makes sense for Trump, a lifelong business executive, to view himself as the salesman in chief. But Trump — who promised to “drain the swamp” of influence and corruption — perpetrated it at the highest levels by helping one of his key donors do business.

The swamp, then, remains quite full.