President Obama and congressional leaders of both parties last night agreed on a broad deal to raise the federal debt limit while imposing 10-year domestic spending caps that would dramatically reshape the fiscal future of energy and environmental agencies.

Though the emerging bipartisan deal has yet to pass muster among rank-and-file lawmakers, its passage ahead of tomorrow's debt-limit deadline appears increasingly likely given the excruciating political pressure to avoid a default. Far murkier is how hard the agreement's $917 billion in discretionary spending cuts -- let alone its promise of across-the-board funding sequestrations if more slashes are not made next year -- would wallop U.S. EPA, the Energy and Interior departments and other environmental programs.

The White House hailed the accord as "a win for the economy and budget discipline," touting its inclusion of $350 billion in decade-long defense cuts as one of several elements aimed at balancing the fiscal pain to come among all sectors of government.

But Democrats' push for new revenue as part of the debt deal, led by a high-profile bid to roll back tax benefits for major oil companies and a separate campaign to revamp ethanol subsidies, failed in the end.

Oil-industry breaks that Obama and green groups blasted as "loopholes" for months are left untouched in yesterday's deal. While a 12-member joint committee tapped to find $1.5 trillion in extra cuts before 2012 is empowered to suggest tax overhauls that could hit major energy companies, Republicans' successful defeat of new revenue proposals this summer leaves them with little incentive to agree to any change that would upset their conservative base.

"There is nothing in this framework that violates our principles," House Speaker John Boehner (R-Ohio) told members of his conference in prepared remarks ahead of a Sunday night conference call. "It's all spending cuts. The White House bid to raise taxes has been shut down.

"And as I vowed back in May -- when everyone thought I was crazy for saying it -- every dollar of debt limit increase will be matched by more than a dollar of spending cuts."

Indeed, the immediate $900 billion debt-limit hike in yesterday's deal would be matched by $917 billion in 10-year cuts achieved through discretionary spending caps that are highly likely to push EPA, DOE, Interior and other agency budgets below the austere levels set for 2011 by the April deal that averted a government shutdown (E&E Daily, July 28).

That $900 billion increase is anticipated to last until early next year, giving Congress until Christmas to approve a $1.5 trillion package of cuts to be hammered out by the new 12-member joint committee. Should that committee deadlock or lawmakers fail to sign off on its recommendations -- which would be guaranteed an up-or-down vote -- $1.2 trillion in spending sequestrations would kick in, "spread between domestic and defense spending," according to a White House fact sheet.

That fact sheet also noted what the Obama administration believes would be a key impetus for the GOP to give more ground than it did in the current debt-limit fight: the Bush-era tax cuts expire at the end of 2012, the same time that the sequestration would begin.

"[T]his compromise does make a serious down payment on the deficit reduction we need and gives each party a strong incentive to get a balanced plan done before the end of the year," Obama said at a press conference last night announcing the deal.

Yet the sequestration is unlikely to please boosters of extra federal energy and environmental spending to shore up the flagging economy, since its new cuts would be designed to hit conservative and liberal priorities equally.

"If the [joint] committee took no action, the deal would automatically add nearly $500 billion in defense cuts on top of cuts already made, and, at the same time, it would cut critical programs like infrastructure or education," the White House fact sheet noted. "That outcome would be unacceptable to many Republicans and Democrats alike -- creating pressure for a bipartisan agreement without requiring the threat of a default with unthinkable consequences for our economy."

While Senate Majority Leader Harry Reid (D-Nev.) and Minority Leader Mitch McConnell (R-Ky.) joined Boehner in throwing their weight behind the deal, the top House Democrat suggested that her sign-off might be slower in coming.

"We all may not be able to support it, or none of us may be able to support it," Minority Leader Nancy Pelosi (D-Calif.) told The Hill in explaining that she would wait to discuss the parameters with her members. "But we'll wait and see."

One of the most green-minded of those House Democrats was already slamming the deal last night. "This deal trades peoples' livelihoods for the votes of a few unappeasable right-wing radicals, and I will not support it," Rep. Raúl Grijalva (D-Ariz.), a senior House Natural Resources Committee member and co-chairman of the Congressional Progressive Caucus, said in a statement.