Lawmakers in the United States have reached out to the Internal Revenue Service (IRS), the nation’s tax collection agency, calling for clearer taxation rules concerning cryptocurrency.

The letter has been signed by Representatives David Schweikert, Darin LaHood, Lynn Jenkins, Brad Wenstrup, and Kevin Brady, who is the chairman of the committee on Ways and Means.

The open letter, dated 19 September, recalls a letter sent to the IRS over a year ago with regards to enforcement actions taken by the IRS against cryptocurrency holders. With some tone of complaint, the letter says that after this time, the IRS has expanded enforcement “without issuing any further guidance for taxpayers”.