A handful of conservative lawmakers in both chambers of Congress are “privately plotting” to force a government shutdown this week to pressure Democrats to defund the Biden administration’s vaccine mandate on private employers, according to Politico.

The news outlet, citing multiple anonymous Republican sources, reported Tuesday that the lawmakers plan to stall the approval of a continuing resolution to fund the government into early 2022 unless Democrats agree to deny money to enforce the mandate.

Congress is set to consider the resolution — which currently includes money to fund the mandate — on Friday. But if the process gets dragged out past midnight, funding will officially expire.