Washington (CNN) President Donald Trump ended a 12-day respite from Twitter assaults about the Justice Department Monday, resurrecting a charge levied by Republican lawmakers that the department and FBI are dragging their feet in handing over documents related to several controversial investigations.

"So sad that the Department of 'Justice' and the FBI are slow walking, or even not giving, the unredacted documents requested by Congress," Trump tweeted. "An embarrassment to our country!"

So sad that the Department of "Justice" and the FBI are slow walking, or even not giving, the unredacted documents requested by Congress. An embarrassment to our country! — Donald J. Trump (@realDonaldTrump) April 2, 2018

The timing of the latest broadside against the Justice Department Monday morning was curious, as FBI Director Chris Wray has pledged to add additional resources working around-the-clock to speed up the document production.

Late last month, the chairman of the House Judiciary Committee issued a subpoena related to a cluster of politically-charged issues, citing "ongoing delays" in producing the documents. The document requests broadly seek materials related to the FBI's investigation into former Hillary Clinton's use of a private email server while secretary of state and the FBI's "potential abuses" of the Foreign Intelligence Surveillance Act in monitoring former Trump campaign aide Carter Page.

The Justice Department said dozens of FBI staffers had been working to produce the documents on a rolling basis, but the House subpoena also included a request for docs about the termination of former FBI Deputy Director Andrew McCabe, which was not in the original request and was a "significant deviation" from the usual process, according to a letter from Assistant Attorney General Stephen Boyd.

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