Originally Published: 20 SEP 21 12:00 ET

Updated: 20 SEP 21 12:02 ET

By Clare Foran, Daniella Diaz and Annie Grayer, CNN

(CNN) -- When the House of Representatives comes back into session this week, averting a government shutdown and addressing the debt limit will be front and center as Democrats contend with divisions within their own ranks over President Joe Biden's sweeping economic agenda.

Staring down a government shutdown and possible default, the question facing House Democrats, who enjoy a narrow majority, is how to solve both issues, and whether to tie them together.

The House is set to take up a stopgap spending bill ahead of the September 30 deadline for government funding to expire. House Democrats are also planning to take action on the debt limit, a move that comes as Congress may only have until mid-October to act before the federal government can no longer pay its bills.

Democratic leaders are up against the clock to decide if they're going to include a debt limit measure in the must-pass spending bill to keep the government open, an option that would essentially dare Republicans to vote no and spark a shutdown. The issue is expected to trigger a major showdown since Republicans so far have not been willing to budge and have repeatedly said they will not vote to raise the debt limit.

House Majority Leader Steny Hoyer announced Friday that the House will move to suspend -- rather than raise -- the debt limit the week of September 20 "to ensure that America pays its bills on time." But in his announcement, the No. 2 House Democrat did not explicitly say whether that would be included as part of the spending bill.

If Democrats add a debt limit hike to the measure, and Senate Republicans block the stopgap spending bill over the debt limit, there could still be enough time to strip the debt limit measure out of the spending bill and pass a clean stopgap spending bill to avoid a shutdown. But the vote would take place perilously close to the shutdown deadline and would likely require cooperation on both sides to process a quick Senate vote. It would leave the debt ceiling problem unresolved, setting up yet another issue to be dealt with in the weeks to come.

The House Rules Committee was supposed to meet Monday to take up the rule governing floor debate of the stopgap spending measure to keep the government open. But a senior Democratic source says it's uncertain if they will move forward on Monday, because the party is still debating whether to add a suspension of the debt limit to the funding bill. The Rules Committee is still slated to meet to take up rules for floor debate over other measures, namely the defense authorization bill.

House Majority Whip James Clyburn, the No. 3 House Democrat, had suggested earlier Sunday Democrats may need to go it alone in passing an increase to the debt limit, but only if "necessary."

"I'm not fine with that, but if that's what it takes, that's what it will take," the South Carolina Democrat told CNN's Jake Tapper on "State of the Union" when asked whether he was comfortable with the debt limit increase passing in a Democrats-only vote.

House Speaker Nancy Pelosi said in a letter to her colleagues Sunday night she wants Congress to address the debt limit in a "bipartisan" way, essentially rejecting the idea of attaching it to legislation that Democrats would pass on their own.

"Congress, as always, is ironclad in its commitment to never letting the full faith and credit of the United States come under threat," Pelosi wrote. "Indeed, since 2011, every time the debt limit has needed to be raised, Congress has addressed it on a bipartisan basis, including three times during the last Administration. When we take up the debt limit this month, we expect it to be bipartisan once more."

Treasury Secretary Janet Yellen called on Congress to raise the debt ceiling in a Wall Street Journal op-ed Sunday, warning that if the US defaults on its debt, it "could trigger a spike in interest rates, a steep drop in stock prices and other financial turmoil."