President Trump and  Texas Gov. Greg Abbott hold a news conference at the Texas Department of Public Safety Emergency Operations Center in Austin on Aug. 29. REUTERS/Carlos Barria

President Trump could request a package of emergency funding to deal with the damage caused by Hurricane Harvey as soon as next week, a senior administration official said, reshuffling the political agenda as the White House scrambles to deal with devastation left by the storm.

The funding package is expected to only be a partial down payment and serve in part to backstop depleted reserves that the Federal Emergency Management Agency had on hand to respond to disasters.

No final decision on the funding request has been made and it could fluctuate based on conversations with lawmakers.

Trump has promised political leaders in Texas that he would do whatever was necessary to help them deal with the widespread flooding brought on by record rainfall in the southeastern part of the state.

Congressional leaders return from a lengthy recess next week. Lawmakers from both parties have said they want to direct emergency aid in the wake of flooding caused by the hurricane, but it’s unclear how long passing such a measure could take.

House Republican aides said White House and congressional staff have started discussing what measures might be necessary to aid storm victims but that there is no firm plan yet for how or when Congress might act.

The White House and congressional leaders have not yet determined how large the initial rescue package should be, but Texas Gov. Greg Abbott said Wednesday that the state will need more financial support than the government extended to Louisiana and Mississippi after Hurricane Katrina hit in 2005.

Trump is planning to meet with Senate Majority Leader Mitch McConnell (R-Ky.), Senate Minority Leader Charles E. Schumer (D-N.Y.), House Speaker Paul D. Ryan (R-Wis.) and House Minority Leader Nancy Pelosi (D-Calif.) on Sept. 6, where the subject of an emergency funding bill is expected to be discussed, the senior administration official said.

Agreeing to an emergency funding bill for Texas could create a separate emergency in Washington. Congress has so far refused to raise the debt ceiling, which is a borrowing limit that effectively prevents the Treasury Department from borrowing additional money. Treasury Secretary Steven Mnuchin has said that if the debt ceiling isn’t raised by Sept. 29, his agency might not have enough flexibility to continue paying all of the government’s bills.

If Congress appropriates billions of dollars in emergency funds for the initial response to Hurricane Harvey, it could deplete Treasury’s already diminished cash reserve balance.

As of Monday, Treasury had $67.8 billion in its cash reserve account, a number that fluctuates daily based on spending and tax receipts. This account had more than $350 billion in it as of January.

Lawmakers were expected to battle later this month over how and whether to raise the debt ceiling, but they could be forced to reach a deal sooner if the Harvey money puts Treasury in a precarious financial position.

One reason the White House is planning to quickly request more money is because the federal Disaster Relief Fund administered by the FEMA had a balance of only $3.8 billion at the end of July, of which $1.6 billion is already designated, according to the most recent federal report.

Senior Senate aides in both parties cautioned that nothing has been agreed to and that they will be taking cues in part from Texas lawmakers, many of whom are still dealing with the immediate effects of the storm. Even one lawmaker, Rep. Brian Babin (R-Tex.), told CNN on Wednesday that he and his family are trapped in their Port Arthur, Tex.-area home.

Abbott told reporters on Wednesday that he expects federal relief costs will far exceed the roughly $120 billion that helped pay for cleanup and response after Hurricane Katrina. Rep. Sheila Jackson Lee (D-Tex.), who represents central Houston, estimated Wednesday night that the costs could exceed $200 billion -- easily topping all previous natural disasters.

"Texas is a big state so the swath that has been damaged meets probably the scale of Sandy," Jackson Lee explained during a phone interview from the George R. Brown Convention Center that is housing thousands of her constituents. "Houston is a very congested city – it’s a very large place geographically, along with the county. We have expansive housing stock, we may have lost 30,000 to 40,000 homes, or at least they’ve been damaged."

Jackson Lee listed a litany of other potential costs: Damaged or lost vehicles; health-care costs to rebuild hospitals and nursing homes; shopping centers that will need to be rebuilt; and cultural losses -- the city's famed art galleries are still submerged so there's no way to assess losses."

"We really think that there are the numbers representing the needs around repairing the homes, redoing the homes, all the things that make a home whole," she said.

Jackson Lee would not say with whom she's specifically speaking about the relief bill but mentioned calls from "across the country" from members of both parties, including House Speaker Paul D. Ryan (R-Wis.), who promised Congress would act quickly.

She described her call with Ryan earlier Wednesday during an appearance at a Houston City Council meeting: “He called me and the one point that he said that there will not be one light of difference — we’ll have some talking points, I’m sure, but — one light of difference to get the funding that we need here in this area.”

Democrats, meanwhile, are pressing congressional Republicans to quickly provide relief to Texas, knowing that FEMA’s Disaster Relief Fund is likely to be depleted quickly in the coming weeks without an emergency influx of money.

Pelosi spoke with Ryan on Monday and White House Chief of Staff John F. Kelly on Tuesday about ensuring that funding is passed quickly “to address immediate needs,” according to a senior aided. Pelosi is also expected to push hard to ensure that the National Flood Insurance Program is reauthorized by its expiration date on Sept. 30.

The idea of providing some early federal relief and passing a more significant aid package later is not new and is rooted in both practical and political necessity — especially given that lawmakers likely need to pass a short-term spending measure to keep the government open beyond late September anyway. After Hurricane Sandy battered the northeast and Mid-Atlantic, Congress passed an initial aid package in late 2012 tied to a short-term spending bill and followed up several weeks later with a larger, more comprehensive bill that paid out the remainder of aid.

“It’s not surprising that they would consider this and makes political sense,” said one senior Democratic aide, who asked for anonymity to discuss ongoing deliberations.