Members of the Congressional Progressive Caucus, betting that their votes will be needed to pass a debt ceiling deal, attempted to insert themselves into the debate Thursday by outlining a host of demands.

In a letter to President Barack Obama, the group insisted that mandatory programs such as Medicare and Social Security should be off limits and that tax increases for wealthy Americans should be included in a deal to raise the debt ceiling and reduce the deficit.

“These points are essential for any deal on the debt ceiling, but more work to rebuild the economy will remain after these negotiations have concluded,” the letter states.

Minority Whip Steny Hoyer (D-Md.) predicted Wednesday that any deal would likely require Democratic votes to pass in the House, and progressives are attempting to capitalize with their letter.

Reps. Raúl Grijalva (D-Ariz.) and Keith Ellison (D-Minn.), co-chairmen of the progressive caucus, signed the letter on behalf of its members, as did Reps. John Lewis (D-Ga.), Mike Honda (D-Calif.), Danny Davis (D-Ill.), John Conyers (D-Mich.) and Luis Gutierrez (D-Ill.). The caucus includes dozens of House Members, as well as Sen. Bernie Sanders (I-Vt.).

The caucus’s demands come as Obama is set to meet at 11 a.m. Thursday at the White House with Democratic and Republican Congressional leaders to determine a way forward on increasing the debt ceiling ahead of Aug. 2, when the Treasury Department warns that the nation will begin defaulting on its debts.

Democrats and Republicans have clashed over revenues and entitlement reform in their negotiations, and Obama has been reticent to strike any line in the sand on what an agreement should look like.