Washington (CNN) President Donald Trump demanded Sunday that his Justice Department look into whether it or the FBI spied on his presidential campaign for political reasons.

"I hereby demand, and will do so officially tomorrow, that the Department of Justice look into whether or not the FBI/DOJ infiltrated or surveilled the Trump Campaign for Political Purposes - and if any such demands or requests were made by people within the Obama Administration!" Trump wrote on Twitter.

I hereby demand, and will do so officially tomorrow, that the Department of Justice look into whether or not the FBI/DOJ infiltrated or surveilled the Trump Campaign for Political Purposes - and if any such demands or requests were made by people within the Obama Administration!

The tweet comes after it was reported that the FBI dispatched a confidential source to speak with some aides to Trump's presidential campaign about its possible ties to Russia, according to multiple reports Friday.

Later Sunday, the Justice Department asked its inspector general to expand its review of the Foreign Intelligence Surveillance Act application process to include whether there was any impropriety or political motivation in how the FBI conducted its counterintelligence investigation of persons suspected of involvement with the Russian agents who interfered in the 2016 presidential election, Justice Department spokesperson Sarah Isgur Flores said in a statement.

Deputy Attorney General Rod Rosenstein said in the statement, "If anyone did infiltrate or surveil participants in a presidential campaign for inappropriate purposes, we need to know about it and take appropriate action."

The New York Times , citing individuals familiar with the matter, reported Friday that the confidential intelligence source interacted with Trump campaign advisers George Papadopoulos and Carter Page. The newspaper said it has uncovered the identity of the informant, who it described as "an American academic who teaches in Britain," but noted that it "typically does not name informants to preserve their safety."

The Washington Post also reported that in addition to Page and Papadopoulos, the source met with Sam Clovis , the Trump campaign's co-chairman, to talk about relations with China. Clovis' attorney told the Post Russia never came up in their conversation.

Although Trump has suggested the source was embedded in his campaign, US officials have told CNN that was not the case.

The officials say that the identity of the source had been closely held at the highest levels of the FBI and intelligence community, and the individual has been a source for the FBI and CIA for years.

Officials from the Justice Department, FBI and Office of the Director of National Intelligence have maintained that turning over that information that congressional Republicans have requested on the source would pose a grave risk to the source's life.

Trump's lawyer, Rudy Giuliani, told CNN that he and the President talked over the weekend and agreed Trump should call for the Justice Department investigation involving the confidential source, adding that he expected the President to send a follow-up letter.

"I mean, he's got to clean house in his agency," Giuliani said. "If there was an informant, we're entitled to know it. We're entitled to know the fact. We're entitled to know what he knows. I think we should know the identity under seal on the confidentiality rules. But, the identity is not nearly as important right now as what did it reveal, because we're convinced it just revealed exculpatory information -- namely, no evidence of a connection with Russia."

Giuliani also said he would want access to the information, adding that he did not see Trump doing an interview with special counsel Robert Mueller unless he had access to details about the confidential source.

"It really would also help the possibility of an interview because I can't imagine we'd allow an interview under the circumstances that there was some kind of informant that planted in our campaign that we didn't know about."

The Justice Department's inspector general and US Attorney John Huber are already investigating whether department protocols were properly followed when the department and FBI applied for surveillance orders on Carter Page pursuant to the Foreign Intelligence Surveillance Act. Those investigations almost certainly include whether anyone was surveilled for "political purposes."

House Republicans have also been pressuring the Justice Department to reveal more information about the source. House Intelligence Committee Chairman Devin Nunes, R-California, said Sunday that he won't meet with department officials until he obtains more documents related to the source.

Earlier this month, Nunes threatened to hold Justice Department officials in contempt of Congress if they don't release documents related to the source that he has subpoenaed. The department consulted with the White House before it sent a letter to Nunes this month declining to turn over the documents, and the White House agreed the documents should not be disclosed.

The President on Saturday called for his Justice Department to allow Congress to review documents related to the source.

"If the FBI or DOJ was infiltrating a campaign for the benefit of another campaign, that is a really big deal," Trump tweeted.

If the FBI or DOJ was infiltrating a campaign for the benefit of another campaign, that is a really big deal. Only the release or review of documents that the House Intelligence Committee (also, Senate Judiciary) is asking for can give the conclusive answers. Drain the Swamp! — Donald J. Trump (@realDonaldTrump) May 19, 2018

Giuliani told The Wall Street Journal on Saturday that federal prosecutors would need to make clear the role played by the confidential source and whether the person had compiled any "incriminating information" about Trump's associates before the President would agree to any interview with Mueller. Otherwise, Giuliani said, Trump could be "walking into a trap."

Democrats respond

House Democrats stood by the Justice Department following the President's demand for an inquiry into the department's actions regarding the Trump campaign.

"This is appalling that President Trump would be so uninformed and that his chief of staff, his counselors, the White House counsel, would allow him to spew into the thinking of Americans that he has any right or authority to dictate to what the Department of Justice does," Texas Democratic Rep. Sheila Jackson Lee, who sits on the House Judiciary Committee, told CNN Sunday afternoon.

"That would skew the independence of the Department of Justice to fairly go after individuals who have broken the law," Lee added. "It is a decision that is made by thoughtful staff lawyers in the Department of Justice in many different areas, from civil rights to antitrust to the criminal justice division. They are all separate divisions and they review information."

California Democratic Rep. Ted Lieu said on CNN that Trump's demand could amount to obstruction of justice.

"If he is trying to influence a federal investigation against him by saying we now need to investigate that investigation, depending on how he does it, that could be obstruction of justice," Lieu said. "He needs to let the investigation against him proceed without any political interference."

Lieu also said in a tweet that he looks forward to the inquiry.

"It will show the professional agents of the @FBI engaged in a counterintelligence operation. Which means @realDonaldTrump associates & perhaps @POTUS himself should be very, very scared of what the @TheJusticeDept knows about what happened in 2016," he added.

Giuliani told CNN when asked that the President's tweet could not be seen as obstructing the case.

"No. I mean, this person either got or didn't get information," Giuliani said. "Nothing is going to affect it. It's been made a matter internally. Now that's it. Nobody can obstruct that at this point. And if you can't answer relevant information under investigation conducted by your department concerning you, I mean, my goodness, that can't possibly be obstruction."