Donald Trump and Nigel Farage. Nigel Farage/Twitter

There is a particular line in the United States Constitution (section one, article nine, to be exact) that is getting a lot of attention right now, though it has never been litigated.

That would be the so-called emoluments clause, which forbids office-holders from accepting compensation from foreign governments.

"No Title of Nobility shall be granted by the United States: And no Person holding any Office of Profit or Trust under them, shall, without the Consent of the Congress, accept of any present, Emolument, Office, or Title, of any kind whatever, from any King, Prince, or foreign State."

One of dozens of proscriptions in the Constitution aimed at fighting corruption, the emoluments clause is one of the only ones that actually applies to the president. Critics of President-elect Donald Trump's potential financial conflicts of interest are pointing to it amid reports about his extensive business dealings with foreign entities, including the state-owned Bank of China.

Some critics point to recent troubling reports — that Trump allegedly asked British politician Nigel Farage to push against wind farm development near a Trump golf course, and that the president-elect reportedly lobbied Argentinian president Mauricio Macri to help expedite a stalled Buenos Ares development — as signs that Trump is already using his clout improperly.

In a meeting Tuesday with the New York Times, Trump seemed to confirm the reports about his talk with Farage.

But Trump's camp is denying the reports about Macri, and the president-elect tweeted on Monday night that his "interests in properties all over the world" have been public knowledge for awhile and that it's "only the crooked media" that is making "this a big deal" now.

In fact, past presidents have worked hard to avoid even the appearance of conflicts of interest: When President Martin Van Buren was gifted horses, rugs, pearls and other goods from the Imam of Muscat, for example, he had a special resolution from Congress passed to let him split the goods up between the State Department and the Treasury, Fordham law professor Zephyr Teachout wrote in the New York Times. President John Tyler behaved similarly.

And other presidents have certainly received scrutiny because of the emoluments clause.

Back in 2009 Republican lawmakers objected to President Barack Obama receiving the Nobel Peace Prize without congressional approval on the grounds that doing so violated the clause. After a lengthy review, the Justice Department concluded that because the prize was awarded by the Nobel Committee, which is not an "agent or representative of the Norwegian government," there was no violation.

Applying this level of scrutiny to Trump could be time-consuming and challenging, given his numerous business dealings around the globe.

The reason that Trump's critics are focusing on the emoluments clause is that a stricter law, preventing financial conflicts of interest in government, actually does not apply to the president, explained Kathleen Clark, a law professor specializing in ethics at the Washington University of St. Louis School of Law.

"The Justice Department construed the conflict of interest statute as not applying to the president and vice president," Clark wrote in an email to Mic.

But the president is bound by the the emoluments clause, Clark said, which amounts to the "prohibition on bribes and illegal gratuities" to the president from foreign states.

As the below tweets from the Atlantic's David Frum points out, when the emoluments clause was written, the U.S. was a very different — and weaker — country than it is today.

The framers were concerned that countries with deeper pockets would try to bribe the president either through gifts or giving them a title.

Critics of Trump's conflicts of interest — including Republican Rep. Sean Duffy and former ethics counsel for President George W. Bush, Richard Painter — have suggested that Trump should simply divest from his businesses.

"It's going to hurt the Trump empire, now that he's a president. It's also going to hurt the U.S. if he's still running the Trump empire," Painter told Mic. "He's gotta make up his mind: Which job does he want? If he doesn't want the job, just let Mike Pence do it."

Constitutional experts agree that without a change, questions about Trump's conflicts of interest will not go away on their own.