(CNN) House Intelligence Chairman Devin Nunes is showing no signs of de-escalating a conflict with the Justice Department over the Russia investigation, hitting the department late Tuesday with an expansive new request for "any contacts" between FBI intelligence sources and over a dozen Trump campaign associates, according to a letter obtained by CNN.

The new request seeks information not only on "FBI informants," but also on "undercover agents, and/or confidential human sources" who interacted with former Trump associates before July 31, 2016 -- the start of the FBI's counterintelligence investigation into connections between the Trump campaign and Russia.

The list of Trump associates Nunes indicated he's interested in includes: Michael Caputo, Sam Clovis, Michael Cohen, Michael Flynn, Corey Lewandowski, Stephen Miller, Peter Navarro, Sam Nunberg, George Papadopoulos, Carter Page, Walid Phares, Joseph Schmitz, Roger Stone and Donald Trump Jr.

On Monday, the Justice Department told Nunes, a California Republican, that he already had the answer to his question about whether the FBI had used informants "against" members or associates of the Trump campaign.

For weeks, President Donald Trump and his allies on Capitol Hill have cried foul over reports that an FBI intelligence source reportedly met with at least three Trump campaign aides during the campaign.

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