(CNN) Democrats are making presidential tax returns a focal point in one of their first pieces of legislation, an effort to build the case to the American people that time is up on President Donald Trump keeping his own tax returns from the public, shutting what could be a window into his personal wealth.

According to two sources familiar with the discussions, Democrats will include a provision in their new bill that would require presidential nominees to disclose 10 years of tax returns shortly after they become the nominee. Vice presidents would also be required to disclose a decade of returns. The tax returns would then be posted on the Federal Election Commission's website for public viewing.

The 10-year requirement is new marker. At the end of last year, Democrats had disclosed H.R. 1 would require presidential candidates to release just three years of tax returns, but a source familiar with the process said that after reviewing precedent, the marker was moved to a decade of returns.

The provision would be included in H.R. 1, a far-reaching bill that makes sweeping ethics changes as well as lays out Democratic priorities on voting rights and health care. The legislation isn't expected to pass the Republican-controlled Senate or be signed by Trump, also a Republican. However, it will give committees an opportunity to set markers on Democratic priorities in the new Congress.

The House Ways and Means Committee had planned to hold a hearing on the tax provision in H.R. 1 at the end of January. However, it could slip into February depending on the outcome of a partial government shutdown that has consumed Washington and left House Democrats spending their early days in the majority negotiating to reopen the government.

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