WASHINGTON (AP) — Retired coal miners and longtime opponents of Obama-era taxes on high-cost health plans are eyeing big wins as top congressional leaders and the Trump White House close in on a deal on a government-wide spending bill that's also carrying lots of overdue Washington business.

The bill would also increase the age nationwide for purchasing tobacco products from 18 to 21.

The legislation would forestall a government shutdown this weekend and give President Donald Trump steady funding for his U.S.-Mexico border fence. The year-end package is anchored by a $1.4 trillion spending measure that caps a difficult, months-long battle over spending priorities.

The roster of add-ons grew over the weekend to include permanent repeal of a tax on high-cost "Cadillac" health insurance benefits and finance health care and pension benefits for 92,000 retired union coal miners threatened by the insolvency of their pension fund. A tax on medical devices and health insurance plans would also be repealed permanently.

The deficit tab for the package grew as well — almost $400 billion over 10 years to repeal the three so-called "Obamacare" taxes alone — with a companion package to extend several business-friendly tax breaks still under negotiation. The Obama-era taxes have previously been suspended on a piecemeal basis.

The late-stage negotiations involved House Speaker Nancy Pelosi, D-Calif., Treasury Secretary Steven Mnuchin, and other top leaders on Capitol Hill. The package is expected to be unveiled at midday Monday for a House vote on Tuesday and the Senate is expected to vote by Thursday or Friday.

The flurry of activity on Capitol Hill was described by Democratic and GOP aides who asked for anonymity because the measure is not public.

The sweeping legislation, likely to be broken up into two packages for political purposes, is part of a major final burst of legislation that's passing Congress this week despite bitter divisions and Wednesday's likely impeachment of Trump. Thursday promises a vote on a major rewrite of the North American Free Trade Agreement.

The increase in the smoking age to 21 does not appear to address broader issues of regulating so-called vaping products, but details of the measure are likely to be released early Monday afternoon, aides said.

Other add-ons include a seven-year extension of the charter of the Export-Import Bank, which helps finance transactions benefiting U.S. exporters, as well as a renewal of the government's terrorism risk insurance program.

Democrats controlling the House would win increased funding for early childhood education and a variety of other domestic programs while the Pentagon would score a record budget.

The outcome in the latest chapter in the longstanding battle over Trump's border wall awards Trump with $1.4 billion for new barriers — equal to last year's appropriation — while preserving Trump's ability to use his budget powers to tap other accounts for several times that amount. That's a blow for liberal opponents of the wall but an acceptable trade-off for pragmatic-minded who wanted increases for domestic programs.