Mr. Trump added in his tweet on Sunday that he will ask DOJ to investigate whether any potential surveillance was ordered "by people within the Obama administration!"
The president's announcement followed a series of earlier tweets on Sunday in which Mr. Trump lambasted the special counsel's Russian Federation investigation as the "world's most expensive Witch Hunt".
Bruce Fein, a former USA associate deputy attorney general, says there are valid reasons for the Russian investigation as too many people from Trump's campaign team associated with foreign officials.
The White House said Monday that top FBI and Justice Department officials have agreed to meet with congressional leaders and "review" highly classified information the lawmakers have been seeking as they scrutinize the handling of the Russian Federation investigation.
The Associated Press reports that Giuliani said that Mueller's probe could end by September 1 if Mr. Trump were to sit for an interview in July, which is the legal team's new working plan.
Giuliania told the AP that the probe's conclusion would be the "culmination of the investigation into the president".
It's a good case study in how outlandish theories created to discredit the Mueller investigation and bolster Trump's position travel from the fringes to the White House.
All may depend on the president and if he'll agree to a possible interview with Mueller.
"It bothers me that they may be an informant in one of the campaigns unless there is a damn good reason", Graham said. Trump allies from Kellyanne Conway to Rudy Giuliani were soon sharing grave concerns about the presence of a spy in the campaign's midst.
Justice Department to examine Trump's claim...
Deputy Attorney General Rod Rosenstein said if anyone did infiltrate the Trump campaign, the DOJ would need to know about it and then take action.
The Justice Department probe had begun in March at the request of Attorney General Jeff Sessions and congressional Republicans.
Benjamin Wittes, whom former FBI Director James Comey showed memos of his meetings with Trump, wrote in a series of tweets that the president's push to investigate the FBI is "nakedly corrupt". On Saturday, Trump tweeted, "If the Federal Bureau of Investigation 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.
Rep. Adam Schiff of California, the senior Democrat on the House intelligence committee, has called Trump's claim of an embedded spy "nonsense".
But Democrats and members of the intelligence community have warned against unmasking a source because they say this puts lives at risk. Yesterday's tweeted announcement from Trump left unclear exactly what action he would request from the Justice Department. "So what we have here is an investigation in search of a crime, which is utterly un-American", said Cortes.
The New York Times reported Friday that a confidential intelligence source interacted with Trump campaign advisers George Papadopoulos and Carter Page.
The probe comes amid an ongoing investigation, headed by Special Counsel Robert Mueller, into alleged collusion between the Russian government and Trump's 2016 election campaign.
It also raised potential scenarios that would threaten the integrity of USA governance: first, that Trump could use his power to go after a political opponent and, second, that he means to derail or even end a criminal probe into his own conduct.
Were Rosenstein to resign under pressure for instance, it could help Trump if he is able to eventually install an official that might be hostile to the Mueller investigation.
Lemire reported from NY.