Story highlights The House and Senate intelligence committees have received some financial data

The Fusion GPS op-ed sparked a fight with congressional Republicans

(CNN) The top Democrat on the Senate Intelligence Committee on Wednesday said that financial issues like money laundering were a matter better suited for the special counsel investigation -- a day after the leaders of an opposition research group called on Congress to probe Trump Organization finances.

Virginia Sen. Mark Warner told CNN that Mueller has "tools we don't have" to investigate financial issues. He did not rule out that his committee was also investigating possible money laundering or other financial issues that could be tied to the Russia probe, but said that it "clearly falls into the scope" of the Mueller investigation.

"At least to me that falls more into what would be criminal activity but those are discussions that will be ongoing," Warner said.

In an op-ed published Tuesday , Fusion GPS co-founders Glenn Simpson and Peter Fritsch said they urged congressional investigators to "look into the bank records of Deutsche Bank and others that were funding Mr. Trump's businesses."

"We found widespread evidence that Mr. Trump and his organization had worked with a wide array of dubious Russians in arrangements that often raised questions about money laundering. Likewise, those deals don't seem to interest Congress," they wrote.

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