Facing the real possibility that Congress won’t do its job, federal agencies are telling many employees that they won’t be allowed to do theirs.

If they haven’t been told already, federal workers will soon learn whether they will be required to report to work or stay home without pay in case Congress fails the nation by not passing a government funding measure.

Unless Congress reaches agreement very soon, a partial government shutdown will occur Tuesday. Agreement is difficult because House Republicans have insisted on tying a fully functional government to killing the Affordable Care Act, a.k.a. Obamacare. But a House-approved bill doing that is going nowhere, as the Senate demonstrated in the bipartisan criticism of the 21-hour talkathon by Sen. Ted Cruz (R-Tex.) against the health-care law.

Senate Republicans don’t like the law, but most of them, unlike their colleagues in the House, know better than to hold the government hostage in an effort to repeal the measure.

So the division in Congress could leave Uncle Sam without funding to run the government and many employees without pay.

House Republicans are cooking up another plan that would allow the government to stay open for now. But the catch is a big one. The new plan would tie a one-year delay of Obamacare, and many other items, to raising the nation’s debt limit. That could lead to another impasse just a short way down the road.

House Republicans seem intent on making the government ungovernable.

Federal employees again would suffer most. The new plan, like those Republicans have pushed before, would increase employee contributions to their retirement benefits.

This unnecessary predicament leaves the nation — and the federal workforce in particular — confused and angry.

Obama administration officials can’t predict how this will play out. In anticipation of a shutdown next week, they informed federal labor leaders in a conference call Thursday that employees would be told who would continue working and who would not.

The administration apparently still does not know how many employees would be furloughed. “They said they are still trying to get their arms around that,” said J. David Cox Sr., president of the American Federation of Government Employees. He estimated that between 800,000 and 1 million employees, out of about 2.1 million, would be furloughed.

Cox and Gregory Junemann, president of the International Federation of Professional & Technical Engineers, said the administration officials indicated that employees who are required to work would be paid “eventually.”

“They can’t guarantee [the workers] will be paid on time,” Junemann said. “They are pretty comfortable with the statement that everybody who works will be paid eventually.” Those furloughed might be paid, but Republicans could move to block that.

The officials “on the call don’t have the ability to make that happen,” said William Dougan, president of the National Federation of Federal Employees.

All this upsets Junemann, who said “a lot of these people are living paycheck to paycheck . . . it’s really immoral what they are doing to the federal workforce.”

Getting paid eventually certainly isn’t as bad as having your compensation cut by being required to pay more for the same level of retirement benefits, as House Republicans are considering, and my colleague Lori Montgomery has reported. The plan now under discussion apparently is like a bill that Republicans used their House majority to approve in December. Had it passed the Senate, the measure would have required federal workers to pay an additional 5 percent of salary over five years toward their retirement contributions, saving the government about $80 billion.

“It is incomprehensible that the House majority once again has decided that if Congress needs to find savings, it will take them from the wallets of federal employees,” said Jessica Klement, legislative director of the National Active and Retired Federal Employees Association. “The proposal suggests we slash the pay of hardworking, middle-class Americans who provide services we all depend on or default on the nation’s financial obligations. Neither of these options is acceptable.”

Colleen M. Kelley, president of the National Treasury Employees Union, said her union “would engage in a strenuous effort to defeat” efforts to increase employee retirement contributions.

“Already, federal employees have contributed more than any other group in our country to deficit reduction and economic recovery — some $114 billion over 10 years — through the continuing three-year pay freeze and higher pension contributions,” she said. “It would be unfair in the extreme to continue turning to this dedicated workforce once again in legislation to raise the debt ceiling, especially since the government is on the brink of default or shutdown because Congress has not done its job.”

Twitter: @JoeDavidsonWP

Previous columns by Joe Davidson are available at wapo.st/JoeDavidson.