Sen. Ron Wyden (Photo: AP)

(Bloomberg) — Congressional Democrats are warning they will fight to prevent President Donald Trump from withholding payments used to subsidize insurance costs for poor Americans under the Affordable Care Act, signalling the issue could become part of the debate to avoid a government shutdown at the end of April.

Top House and Senate Democratic leaders are pushing to guarantee the cost-sharing reduction subsidies as part of a spending bill that must be approved by April 28, the last day of government funding under current law, according to three Democratic aides.

(Related: Trump Threatens Health Subsidies to Poor to Force Talks)

Sen. Ron Wyden of Oregon, the top Democrat on the Senate Finance Committee, also signaled a tough stance Thursday, saying Democrats “will not negotiate with hostage takers.”

Trump told the Wall Street Journal Wednesday that he might withhold the cost-sharing-reduction payments to force Democrats to negotiate changes to the ACA, which Republicans have been seeking to repeal.

The three Democratic aides, who spoke on condition of anonymity, said both Senate Minority Leader Chuck Schumer and House Minority Leader Nancy Pelosi agree that cost-sharing-reduction payments must be included in the omnibus spending bill being negotiated as permanent, mandatory spending.

Those payments to lower-income people have been at the center of an almost three-year legal battle between Republicans and Democrats.

Shutdown Threat

The Democratic aides made clear that the payments could become a potential shutdown issue, since Democratic votes will be needed to pass the bill in the Senate, and perhaps in the House.

Negotiations over that bill, which lawmakers will have only five days to pass when Congress reconvenes on April 24, are already increasingly complicated. Some Republicans are prepared to fight for Trump’s request for funding to begin building a border wall, which Democrats have made clear they will oppose. Trump also is calling for a provision that blocks federal funding for “sanctuary cities.”

On cost-sharing reduction payments, Democrats may find some Republican allies.

Rep. Greg Walden, an Oregon Republican who chairs a key health committee, said in late March that his preference is to include the money in the spending bill, as well.

On Thursday, two former Senate Majority leaders, Republican Bill Frist of Tennessee and Democrat Tom Daschle of South Dakota, made a call on behalf of the Washington D.C.-based Bipartisan Policy Center, to extend the subsidy payments.

“It is clear that the withdrawal of cost-sharing subsidies provided through the Affordable Care Act would destabilize this already fragile market,” they said in a joint statement.

— Read GOP Seeks Way to Pay Insurers So More Don’t Drop ACA Plans on ThinkAdvisor.

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