Mueller's probe was already investigating Kushner's contacts with Russian officials during Trump's presidential transition period.
Robert Mueller III, the special counsel investigating Russian interference in last year's presidential election, has boosted his team of lawyers to 13 and plans to hire several more, his spokesman, Peter Carr, said on Friday.
Friday, the Federal Bureau of Investigation formally denied the FOIA request for the Comey memos, citing a law enforcement exemption.
Rosenstein, in office for less than two months, is the top Justice official overseeing the probe because Attorney General Jeff Sessions has recused himself. A former prosecutor, Dowd may be best known to the public for leading investigations on behalf of Major League Baseball, including a probe of allegations of improper gambling by baseball player Pete Rose that preceded Rose's lifetime ban.
The former House Speaker pointed to a column from former Bush adviser Karl Rove Thursday that warned about Mueller not focusing on the Russian Federation investigation.
Asked about the prospect and his potential need to recuse during his testimony before the Senate Appropriations Committee, Rosenstein said only, "I am working with career professionals who know these rules and are responsible for enforcing these rules, and I can assure you that we're going to do the right thing, and we're going to defend the integrity of that investigation". He is reportedly interviewing three top intelligence officials - Director of National Intelligence Dan Coats, National Security Agency Director Mike Rogers and retired deputy NSA director Richard Ledgett - as part of the probe as early as this week. The official demanded anonymity because the official was not authorized to be named discussing the deliberations.
Mueller's investigation is still in a relatively early phase, and it is unclear if any criminal charges will be brought when it is complete, the Post pointed out.
The tweet, which seems to confirm that Trump himself is under investigation, appears to reference Deputy Attorney General Rod Rosenstein as "the man" investigating him.More news: Ken Starr warns Trump against firing Mueller
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The White House has directed questions for details to outside legal counsel, which has not responded.
The transition official said the organization has also separately asked the General Services Administration to preserve records from the Trump transition that were transferred to its facilities after Trump's inauguration. Cohen has worked for Trump since the mid-2000s and was active in the campaign.
It was previously reported that investigators were looking into Kushner's December meetings - which were not originally disclosed on his security clearance application - with Sergey Kislyak, the Russian ambassador to the USA, and Sergey Gorkov, a graduate of the academy of the KGB's successor organization and the head of a state-owned Russian bank that is subject to American sanctions.
Trump also lashed out at the media, on a day that aides hoped would be focused on his decision to undo some of Barack Obama's detente with Cuba.
"Why is that Hillary Clintons family and Dems dealings with Russian Federation are not looked at, but my non-dealings are?" he asked at one point. "Nice", Trump wrote in his first tweet.
President Donald Trump is telling his Twitter followers that they are witnessing the "single greatest WITCH HUNT in American history".