Sherrod Brown is pressing the Treasury Department to obtain and vet a list of President Trump's business associates for improper ties to Russia or other countries.

The Ohioan, the top Democrat on the Senate Banking Committee, wrote Treasury Secretary Steven Mnuchin Tuesday asking if the department has examined if any Trump Organization business ties run afoul of U.S. sanctions, anti-corruption or anti-money laundering rules.

Brown has been pushing for the Treasury, which is responsible for enforcing sanctions and cutting off terrorist funding, to conduct a review of Trump's business associations in Russia and elsewhere. Most recently, he asked Mnuchin directly for such a review at a hearing earlier in May.

To date, though, his staff says that he has received only a brief letter from Treasury staff that Brown said in Tuesday's letter "altogether missed the point of my inquiry." That letter was sent before the hearing, and Brown hasn't received anything since the hearing, according to a spokesman. The Treasury did not immediately respond to an inquiry about the Democrat's request.

Democrats have sought to use what leverage they have to force the administration to hand over whatever documents it might have related to Trump's businesses and Russian officials or other counterparties.

For his part, Trump has claimed that he doesn't have any business interests with Russia beyond what has been disclosed, such as the 2013 Miss Universe pageant.