Congress returns from a two-week break facing a deadline to keep the government operating while President Donald Trump presses harder for some legislative accomplishments as his first 100 days in office wind to a close.

The week is shaping up to be a collision of needs between the two, and time is quickly running out on both.

Passing funding to avoid a government shutdown appeared to be an easy task just weeks ago, but new stumbling blocks have arisen in recent days as Trump has added new demands on items like the border wall and increased military spending.

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Government funding ends Friday, allowing only three full days of legislative activity after the House returns late Tuesday night, and the last-minute controversial requests from the administration are threatening to make a deal harder to reach.

At the same time, Trump is pushing Congress to move quickly on another attempt to pass a repeal bill of the Affordable Care Act, even though House Republicans aren't unified on a path forward.

To add more to Congress' plate, Trump told The Associated Press last week that he intends to unveil his plan to overhaul the tax code, another priority for Republicans but a gesture that caught Republican congressional leaders by surprise.

All of this is making for a busy week. Here are the top issues facing Congress when it returns:

Funding the Government

Because Congress failed to come together on an appropriations bill for 2017 last year, its passed a short-term measure called a Continuing Resolution, or CR, that funds the government at 2016 levels. But the CR runs out on Friday, giving Congress a hard deadline to pass a comprehensive funding bill to finish the current fiscal year.

With time running out and the last-minute demands by the Trump administration complicating negotiations, it is likely that Congress, which isn't interested in a government shutdown, will pass another short-term CR to keep the government open for a week or two.

Aides to Republican and Democratic members involved in hammering out a funding bill have admitted that talks had been progressing well until last week, when the Trump administration demanded politically toxic measures be put into the measure.

Those include $3 billion for border security and the construction of a border wall, as well as $30 billion more for defense spending. The administration also said it wants to withhold funding for some subsidies in the Affordable Care Act that help low-income people afford health care.

Both Republicans and Democrats in Congress have expressed displeasure with the administration's late demands.

Rep. Tom Reed, R-New York, said politics should be kept out of the funding bill. "I hope we can avoid these ideological issues and focus on keeping the lights on," Reed said Friday on MSNBC.

"We've asked the president not to interfere. If he doesn't interfere, we can get this done," said Senate Democratic leader Chuck Schumer of New York. "So we ask him to let us do our work and to not throw in some last-minute poison pills that could undo it and we can get this done."

@realDonaldTrump The Democrats don't want money from budget going to border wall despite the fact that it will stop drugs and very bad MS 13 gang members.

Health Care

As if working up to the eleventh hour to keep the government open wasn't enough, the White House is pushing the House to vote on a Republican health care bill to undo much of Obamacare.

Trump, who underestimated the ideological splits among House Republicans on the last go-around, would still like them to pass their signature campaign promise — repealing Obamacare — before his 100th day on Friday.

An amendment revealed last week is meant to be a compromise for the most conservative members to agree to support the bill. It's not impossible for a vote on health care to come up this week, but leadership isn't likely to let members vote on it unless they have a majority — 216 Republicans — to pass the bill.

In a conference call with Republican members over the weekend, House Speaker Paul Ryan of Wisconsin made it clear that while work on health care continues, the focus of the coming week will be on keeping the government open.

Tax Reform

Another wish-list item for Republicans is tax reform, which, according to their original plan, was supposed to be presented as early as this month or May. But the failure of the health care bill has complicated the timeline, pushing tax reform back to the fall.

Still, Trump, eager for the aura of success, said he would unveil his plan for corporate and individual taxes this week.

A plan is not legislation, however, and Ryan has said tax reform is much more difficult to achieve without repealing the nearly trillion dollars of taxes in the Affordable Care Act.

2018 Appropriations

While Congress is still wrangling over 2017 funding, it must make progress on 2018 funding. Congress' main responsibility is to fund the government, and if the Republicans, who ran on the platform of fiscal responsibility, want to have government funding in place for the next fiscal year on time, their work on a dozen appropriations bills must be complete by Oct. 1.

Debt Ceiling

By August, the government is expected to reach the limit on its ability to borrow money — or pay for government programs like Social Security and air traffic controllers — forcing Congress to raise the debt ceiling.

It's been a controversial vote in recent years as Republicans used it to paint President Barack Obama as fiscally irresponsible and nearly forcing a government shutdown over it. While the deadline isn't pressing at the moment, it's another part of a complicated summer calendar.

But it will be the first time Congress will have to raise the debt ceiling with a Republican in the White House. It'll still be a difficult vote for conservatives who voted against it in the past.