President Trump will end key payments to insurers selling ObamaCare plans, the White House announced late Thursday, marking Trump’s most aggressive move yet to dismantle the law after multiple GOP efforts to repeal and replace it failed this year.

The Trump administration has continued making the the disbursements to insurers, known as cost-sharing reduction payments, on a monthly basis. But Trump had consistently threatened to end the payments, which are worth an estimated $7 billion this year.

“Based on guidance from the Department of Justice, the Department of Health and Human Services has concluded that there is no appropriation for cost-sharing reduction payments to insurance companies under Obamacare. In light of this analysis, the Government cannot lawfully make the cost-sharing reduction payments,” the White House said in a statement late Thursday night.

The payments were created as part of the Affordable Care Act but were then the subject of a lawsuit by House Republicans during the Obama administration. A federal court ruled the payments were being made illegally, but the Obama administration appealed.