Disputes over defense and healthcare spending are threatening to hold up a spending bill that has to be passed next week in order to avoid a partial government shutdown, the same week Republicans are hoping to finish a major tax reform bill.

Senate Minority Leader Chuck Schumer, D-N.Y., has pledged to block a House proposal to fund the government through Jan. 19. Schumer opposes the plan because it includes full-year funding for the Department of Defense that exceeds federal spending caps, but doesn't include any such language for domestic spending.

Democrats want parity for domestic spending, but Republicans are hoping to get to it next year. Democrats aren't happy with that.

“Lifting those spending caps in equal measure has been the basis of successful budget agreements going back several years,” Schumer argued on the Senate floor Thursday. “It has been parity between defense and nondefense for the three last budget negotiations and that is how it ought to stay. That is what brought us to good agreements, that’s what averted shutdowns.”

Schumer called the House proposal “a dead-end strategy” and pledged the measure “will quickly fail in the Senate.” Republicans can pass what they want in the House, but Democrats still have the power to block legislation in the upper chamber, so getting some kind of agreement will be needed to overcome that hurdle.

One way of getting around the problem, at least initially, is to have the Senate pass a short-term spending bill, or continuing resolution, that leaves out the extra funding for defense and keeps spending levels at 2017 levels for all of the government until Jan. 19. Appropriators told the Washington Examiner they anticipate the Senate to do that, which could initially get around the problem, because Senate Democrats would presumably accept that bill as a short-term answer.

But that plan could run afoul of House conservatives and defense hawks, who are insisting the short-term CR include full-year defense spending. If Republicans push to include the defense spending, it would lead to the same impasse between House and Senate versions of the bill.

“If the Senate sends back a clean CR, you’d lose some Republican votes, you’d presumably get some Democratic votes, you just don’t know,” Rep. Tom Cole, R-Okla., a top member of the House Appropriations Committee, told the Washington Examiner.

The spending battle will unfold over the next week, as current spending authorization expires Dec. 22. It's a jammed calendar, as Republicans will be using the week to pass its tax reform bill.

But House Republicans are likely to take up tax reform legislation only after the Senate passes the measure, which Senate Majority Whip John Cornyn, R-Texas, predicted will happen on Tuesday.

The spending battle is complicated by factors other than just defense money. House Minority Leader Nancy Pelosi, D-Calif., said Thursday she will not support a clean CR because the measure lacks Democrats’ wish-list items, which she said were provided to President Trump at a recent White House meeting.

The House CR includes federal funding for the Children’s Health Insurance Program, or CHIP, but Democrats don’t like the way it is written and say it will draw money from other critical health programs for children.

“Children's health paying for children's health,” Pelosi said Thursday.

Another issue is additional federal funding for states and territories damaged by recent hurricanes and wildfires.

“Our members very much want to see an agreement on a disaster supplemental before we leave,” House Speaker Paul Ryan, R-Wis., said Thursday. “So that is something we're working toward.”

Democrats are also insisting the spending deal include extra money for states to battle opioid addition.

“So let's see what they send over,” Pelosi said, referring to the Senate. “Maybe they'll add some things to it.”