The source who spoke to CNN on Thursday said the subpoena's intention was to "clean up" and to ensure that all related documents are handed over to the special counsel.

White House special counsel Ty Cobb had no comment. Alan Futerfas, an attorney for the Trump Organization, said in a statement that Thursday's reports are "old news and our assistance and cooperation with the various investigations remains the same today." White House press secretary Sarah Sanders declined to comment on the subpoena, reiterating the administration's position that there was "no collusion" between the Trump campaign and Russia and referring further questions to the Trump Organization.

The Times, citing two people briefed on the matter, said the subpoena was delivered "in recent weeks."

The Times said special counsel witnesses had been asked recently about a potential real estate deal in Moscow, and that investigators have questioned witnesses about the flow of money from the United Arab Emirates to the United States.

CNN has reported that George Nader, a Middle East specialist tied to secret meetings between the UAE and Trump associates, is cooperating with Mueller.

The Times report said the subpoena is related to records prior to Trump's run for office. CNN reported in January that the Trump Organization had provided documents largely from the period after Trump announced his run up to his inauguration.

Lawyers for Trump said last May that over the past decade, Trump's unreleased federal tax returns do not show any income from Russian sources "with a few exceptions."

Sources previously told CNN that Mueller's investigators had been asking witnesses about Trump's business activities in Russia prior to his presidential run, including an unrealized attempt for a Trump Tower in Moscow. Last week, as he took to national airwaves for a series of interviews claiming he would defy a grand jury subpoena in the probe, former Trump aide Sam Nunberg told CNN he suspected investigators wanted to know more about the 2013 Miss Universe pageant Trump hosted in Moscow.

News of the subpoena broke shortly after the Trump administration announced a new raft of sanctions on Russia, including Russian nationals previously indicted in the special counsel probe.

His former campaign chairman Paul Manafort faces more than 300 years in prison if he's convicted of charges stemming from Mueller's investigation that are unrelated to alleged Russian meddling in the election.