House Speaker Ronald Mariano and Senate President Karen Spilka answer reporters' questions Monday at a press availability in the governor's office.

BOSTON — House and Senate leaders are working together on how to roll out a plan for spending billions of dollars of federal stimulus, but they are also grappling with another wrinkle as their mid-November target approaches: action and inaction in Washington, D.C.

On the eve of the Legislature's final fall hearing about American Rescue Plan Act funding, Senate President Karen Spilka said state lawmakers are keeping one eye on an infrastructure bill that has been bouncing around the nation's capital in different forms for months.

Approval of a federal infrastructure package — with proposals ranging from $1.5 trillion to $3.5 trillion — would steer a significant pot of money to Massachusetts and could tackle a wide range of topics including road and bridge maintenance, child care affordability, and climate resilience. However, the package's fate is tied up in continuing partisan battles, with Republicans balking at a push for major social spending.

Some of the spending areas in the infrastructure bill have also drawn attention on Beacon Hill, where an ARPA bill is quietly being assembled, and Spilka said she is wary about possible overlap.

"We all are hearing about an infrastructure bill on the federal level," Spilka told reporters after meeting privately with House Speaker Ronald Mariano, Gov. Charlie Baker and Lt. Gov. Karyn Polito. "Particularly things like culverts or other areas might be included in the infrastructure bill, so there is a feeling that as we're doing this, it's also giving the federal government time to finalize their bills, so if we are getting money directly from the federal government on some of those areas, we don't duplicate the spending or spend it unwisely on areas we are spending other money on."

Spilka stressed that passage of an ARPA spending bill will not depend on the outcome of federal proceedings, saying that legislative leaders are "still planning" to carve up at least part of the roughly $4.8 billion pot before they wrap up formal business for the year in mid-November.

In the meantime, a series of legislative listening sessions about how to use the ARPA money will draw to a close with the final hearing on Tuesday, and the House and Senate budget chiefs are talking privately about next steps.

"The chairmen of Ways and Means in the House and the Senate are both negotiating now on how to roll out this planned spending for a large portion of the money," Mariano said. "We will continue to listen and begin to negotiate on the best way to roll this out to make sure the money is spent efficiently and in a transformative way."

House and Senate leaders often roll out separate versions of spending proposals in each branch and dig in behind their ideas, so early negotiations on an ARPA bill could smooth its path to Baker's desk this fall.

Mariano said the House and Senate still have not agreed to the size of the forthcoming spending package, though legislative leaders have indicated they plan to allocate only a portion of the pot this fall. Spilka added that legislative leaders are waiting until the end of the committee hearings to determine priorities for immediate spending.

The Baker administration has been pushing for months to use about $2.9 billion of the ARPA money on housing, infrastructure, workforce training and other areas the governor flagged as urgent.

Since the Legislature asserted its control over the ARPA pursestrings earlier this year, Baker has continued to make the case for prompt action. When a reporter asked Mariano and Spilka on Monday about the timeline for action, Baker interjected, "I'd like an answer to that question, too."

The Republican governor said that many of the most substantial ideas floated will not "happen overnight," cautioning against getting too lax because of a 2026 deadline to spend the money.

"You can't start the process until you have an appropriation," he said. "I think a bunch of these things, to truly be transformational, could take a while. I certainly get and understand the Legislature's desire to deliberate on this, and I certainly learned a lot from the testimony that's been offered, but at the same time, I would say a lot of the folks who testified testified on behalf of a lot of the elements and stuff that we proposed back in May."

Responding to Baker, Spilka said the legislative hearings provided "an opportunity for us to give not only our members but the public and advocates a chance to directly respond to these issues."

Under legislative rules, the branches will wrap up formal business for the year on Nov. 17 and will then meet informally — when opposition from a single member can halt a bill's progress — until January, when a seven-month stretch of formal sessions starts up and runs through July.

The Legislature has a sizable to-do list ahead of that deadline, including an ARPA bill, a fiscal year 2021 closeout budget and approval of new legislative districts following the 2020 Census.

Both branches plan to meet in formal sessions on Wednesday.

The Senate is scheduled to tackle an election reform bill that would make mail-in voting and expanded early voting permanent while authorizing same-day voter registration, and the House plans to consider Senate-approved legislation establishing cage-free egg standards (S 2481).

Animal rights organizations and commercial egg farmers — former opponents on a 2016 ballot question that voters approved — have been pushing for reforms to a cage-free law set to take effect in January, warning that inaction would limit the available supply of eggs.