Two House committees have stepped up their investigation of Donald Trump’s business operations by issuing subpoenas for a range of documents from the institution that has long been his main financial prop, Deutsche Bank.

The move comes from the intelligence committee and financial services committee of the House, both of which have been controlled by the Democratic party since January. Leaders of the two panels stressed the urgency of the inquiries.

Maxine Waters, who heads the financial services committee, said the investigation was exploring “the use of the US financial system for illicit purposes”, including the potential involvement “of the president and his associates”.

On the intelligence committee side, the panel’s chairman, Adam Schiff, said subpoenas had been sent to “multiple financial institutions” including Deutsche Bank, which he emphasized was cooperating.

In past comments Schiff has indicated that the purpose of the inquiries was to see whether “any foreign actor has sought to compromise or holds leverage, financial or otherwise, over Donald Trump, his family, his business, or his associates”.

Deutsche Bank said it was in a “productive dialogue” with the committees.

The new subpoenas, first reported by the New York Times, come as Washington is braced for the release of a redacted version on Thursday of the Mueller report into Russian interference in the 2016 presidential election. On the back of a four-page summary written by his handpicked attorney general, William Barr, Trump has claimed that he has been “exonerated” of any claims of collusion or other wrongdoing.

But he still faces political peril when the entire nearly 400 pages of Robert Mueller’s report come out, redactions notwithstanding. And as the actions of the two powerful committees show, Democratic leaders in the House remain determined to hold the president to account over his financial dealings.

Deutsche Bank has been increasingly identified by congressional investigators as a possible vulnerability for Trump. In the wake of bankruptcies of some of his companies in the 1990s, Trump was shunned by many US lenders and turned to the German bank for help.

Over the years he has borrowed more than $2bn from the institution. The Trump Organization is believed to have about $300m in loans still outstanding.

In return, the bank has been willing to lend to Trump, given its own problems in the wake of a succession of scandals including multimillion-dollar fines for failure to prevent money laundering of Russian money.