WASHINGTON, May 21 (Xinhua) -- The U.S. Department of Justice said on Monday that it has asked its watchdog, the Inspector General, to probe President Donald Trump's accusations that his campaign had been "infiltrated or surveilled" by the FBI during the 2016 elections.

The Department has asked the Inspector General to "expand the ongoing review of the FISA (the Foreign Intelligence Surveillance Act) application process to include determining whether there was any impropriety or political motivation" in the FBI probe, DOJ spokeswoman Sarah Isgur Flores said in a statement.

As always, the Inspector General will consult with the appropriate U.S. Attorney if there is any evidence of potential criminal conduct, she added.

"If anyone did infiltrate or surveil participants in a presidential campaign for inappropriate purposes, we need to know about it and take appropriate action," said Deputy Attorney General Rod Rosenstein, who oversees special counsel Robert Mueller's investigation into alleged Russian meddling in the U.S. elections and the Trump campaign's possible involvement.

Trump met Monday afternoon with Rosenstein, as well as FBI Director Christopher Wray, White House Chief of Staff John Kelly and Director of National Intelligence Dan Coats to discuss their response to congressional requests on a range of topics, White House Press Secretary Sarah Sanders told NBC News.

"It was also agreed that White House chief of staff Kelly will immediately set up a meeting with the FBI, DOJ, and DNI together with congressional leaders to review highly classified and other information they have requested," Sanders said.

The Justice Department's internal watchdog, the Inspector General, is already examining Republican complaints of FBI misconduct in the early stages of the Russia investigation.

Trump had been tweeting similar allegations for days. On Friday, he tweeted: "Apparently the DOJ put a Spy in the Trump Campaign. This has never been done before and by any means necessary, they are out to frame Donald Trump for crimes he didn't commit."

"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 tweeted on Sunday.

The New York Times reported on Saturday that at least one government informant met several times with two Trump campaign aides who were suspected to have contacts linked to Russia.