"Deutsche Bank always cooperates with investigating authorities in all countries", the bank told Bloomberg in a statement Tuesday that did not provide any additional information. "No subpoena has been issued or received".
Mueller and his team spent $6.7 million between May and September, according to a new report released by the Department of Justice. Deutsche Bank may be glad it's being forced to hand over information.
In June, President Trump disclosed that he owes the bank roughly $130 million.
President Donald Trump visits the Church of Jesus Christ of Latter-Day Saints Welfare Square food distribution center in Salt Lake City, Utah, U.S., December 4.
The Guardian, citing German newspaper Handelsblatt, reported that the bank has since cooperated with the request and handed over banking records to investigators.
Trump got a $106 million loan from Deutsche Bank in 2011 to buy Doral, the golf resort in Miami, according to property filings with the local land register.
That figure includes a $170-million loan Trump took out to finish a hotel in Washington. The case was settled in 2009.
Deutsche Bank has been served.
In May, Deputy Attorney General Rod Rosenstein appointed Mueller to serve as special counsel for the Justice Department, and to oversee the investigation into "any links and/or coordination between Russian government and individuals associated with the campaign of President Donald Trump, and any matters that arose or may arise directly from the investigation".
It was reported earlier that as part of his probe into possible collusion between Russian Federation and the Trump campaign, Mr Mueller asked Deutsche Bank to share data on accounts held by Mr Trump and his family.
It was also revealed days ago that White House Senior adviser Jared Kushner met with Mueller's team as part of its Russian Federation meddling probe. It is not clear whether the investigation has Trump's tax returns, but Mueller is authorized to access such documents.