President Trump weighed in on the so-called "Trump dossier," calling on the federal government to "immediately" release any information it has on who might have paid for it.

"Officials behind the now discredited 'Dossier' plead the Fifth. Justice Department and/or FBI should immediately release who paid for it," the president tweeted Saturday afternoon, not long after he returned to the White House after spending the afternoon at his golf club in Virginia.

His tweet appears to be in reference to a House Intelligence Committee hearing this week in which two top officials with Fusion GPS, the company responsible for the creation of the dossier invoked their Fifth Amendment rights and didn't answer questions, according to a lawyer who represents them.

The two Fusion GPS partners were Peter Fritsch and Thomas Catan.

Earlier in the day Saturday it was reported by the Daily Beast that the chairman of the intelligence panel, Rep. Devin Nunes, who stepped aside from leading the committee's Russian investigation, issued a subpoena on Fusion GPS's bank for records in an attempt to track down the who paid for the dossier. The firm asked a judge to to halt the bank from complying with the subpoena.

The dossier publicly rose to prominence near the end of the 2016 campaign after it was published in full by Buzzfeed in January. Most of the claims in the dossier, which appears to show Trump's ties to Russia, remain unconfirmed.

Sen. Richard Burr, chairman of the Senate Intelligence Committee, recently expressed frustration about not being able to speak with or interview former British spy Christopher Steele, who is believed to have authored most of the dossier and therefore is called by his name.

Meanwhile, Senate Judiciary Chairman Chuck Grassley, R-Iowa, has expressed concerns about Fusion GPS founder Glenn Simpson, who previously interviewed with the Senate Intelligence Committee for 10 hours.

Specifically, Grassley is interested about how when Simpson was assembling the document in 2016, he might have shared some of his material with the British intelligence services, who then could have passed on that information to American intelligence agencies without specifying their source.

As previously reported by the Washington Examiner, if the FBI had a copy of the document, as Grassley's theory goes, any notification from British intelligence services about the information would have looked like independent corroboration of allegations, when instead, Simpson would have been the sole source.

Some conservative media outlets have even theorized that the dossier may have been the original factor that sparked investigations by the House and Senate intelligence committees.

Trump also remarked Saturday on the "fake news" reports about the money spent by the Russians on Facebook ads during the 2016 campaign.

"Keep hearing about 'tiny' amount of money spent on Facebook ads. What about the billions of dollars of Fake News on CNN, ABC, NBC & CBS?", he tweeted.

Facebook announced in early September that it discovered the sale of $100,000 in ads during the 2016 presidential campaign to accounts linked to a Russian company. Facebook turned over 3,000 ads connected to the Kremlin to Congress this month. The company previously had disclosed descriptions of the ads to special counsel Robert Mueller, who, along with congressional investigators, is looking Russian interference in the 2016 election and whether the Trump campaign colluded with the Kremlin.

The Senate Intelligence Committee has invited Twitter, Facebook, and Alphabet, Google's parent company, to testify publicly on Russia-related matters on Nov. 1.

Todd Sheperd contributed to this report.