Sen. Susan Collins, R-Maine, who has been moderating bipartisan negotiations on immigration, arrives at the Senate just before the announcement of an agreement in the Senate on a two-year, almost $400 billion budget deal that would provide Pentagon and domestic programs with huge spending increases, at the Capitol in Washington, Wednesday, Feb. 7, 2018. The spending deal did not include a plan to protect the "Dreamers" who have been protected by the Deferred Action for Childhood Arrivals program, at the Capitol in Washington, Wednesday, Feb. 7, 2018. Credit: J. Scott Applewhite | AP

Senate leaders announced a bipartisan two-year budget agreement Wednesday that would provide nearly $300 billion in additional funding, a step likely to avert a Friday government shutdown and end a months-long impasse on spending priorities.

The plan would also suspend the federal debt ceiling until March 2019, according to Sen. Roy Blunt of Missouri, a member of the GOP leadership team. It also would provide hurricane and wildfire disaster aid. Blunt said he expects a Senate vote on Thursday.

The dollar rose on the deal, as did yields on the 10-year U.S. Treasury.

Majority Leader Mitch McConnell of Kentucky called the plan a “significant agreement” that gives both parties what they want. It includes a long-sought defense spending boost that was the top goal of Republicans who lead both chambers in Congress and gives more funding for domestic programs sought by Democrats.

Defense spending would increase by $80 billion over current law in this fiscal year and $85 billion in the one that begins Oct. 1, according to a congressional official familiar with the plan. Non-defense spending would rise by $63 billion this year and $68 billion next year.

Secretary of Defense James Mattis told reporters at the White House that he’s optimistic that Congress will give the Pentagon the funding it needs.

Lawmakers intend to combine the two-year spending deal with a short-term measure to keep the government operating when current funding runs out at the end of the day Thursday. Like the House-passed short-term bill, the Senate measure would fund the government through March 23 while lawmakers fill in the details on longer-term spending.

Senate Minority Leader Chuck Schumer of New York, speaking on the floor after McConnell, said the agreement was completed “without a great deal of help from the White House.”

“I believe we have reached a budget deal that neither side loves but both sides can be proud of,” Schumer said.

Maine Sen. Angus King said in a statement the agreement “contains many important provisions for Maine, including a reauthorization of community health centers that provide quality care to more than 200,000 Maine people, additional funding to fight the opioid epidemic and infrastructure funds that can be used to improve rural broadband access.”

He also expressed concern about the increase in spending which “comes on the heels of a tax plan that is expected to raise the national deficit by approximately $1 trillion.”

“Now that we’ve reached a bipartisan budget deal, I hope we can harness this momentum to get serious about putting our fiscal house in order,” said King.

One complication is House Minority Leader Nancy Pelosi of California, who was part of the negotiations on the agreement. She said earlier Wednesday that House Democrats won’t back the plan without a commitment from Speaker Paul Ryan of Wisconsin to allow an open debate on immigration legislation, similar to a promise made by McConnell.

Some conservative Republicans, including members of the House Freedom Caucus, are threatening to vote against the deal because of the higher spending for non-defense programs. That means as many as 100 Democratic votes may be needed to get it through the House.

GOP Rep. Mo Brooks of Alabama said he’ll vote “hell no” on the measure.

“The Republican Party seems to be the party of big government in this day and age,” said Brooks, though he added he doesn’t think there’s enough opposition to sink it.

Pro-immigration Democrats pushed Pelosi to demand an open debate on immigration legislation rather than being forced to vote on a Republican-only proposal.

Rep. Luis Gutierrez, an Illinois Democrat, said a budget deal is unacceptable without protection for undocumented immigrants brought to the U.S. as children, who have been covered under the soon-to-end Deferred Action for Childhood Arrivals program.

“That would be a complete betrayal,” he told reporters, adding that “a lot” of Democrats would feel the same.

McConnell reiterated his promise to allow an open debate on immigration legislation “that will be fair to all sides.” He said it will start with essentially a blank slate and both Democrats and Republicans will be able to offer amendments for a vote.

The higher spending would add to an expanding federal budget deficit that Steve Bell, a former Senate Budget Committee staff director, forecast would reach as much as $1 trillion next year.

Second-ranking Senate Republican John Cornyn of Texas said the disaster relief package will be between $80 billion and $90 billion.

The deal would repeal an Obamacare board charged with controlling health-care costs, which has long been criticized by Republicans.

Schumer said the deal would extend the Children’s Health Insurance Program for 10 years, four more than the extension Congress just enacted.

The plan includes $20 billion for infrastructure over two years, including roads and drinking water, he said. There’s also $6 billion to combat opioid abuse and improving mental health, $2 billion for research at the National Institutes of Health, and $4 billion for college affordability.

The deal would be at least partly paid for by cuts to mandatory spending programs elsewhere in the budget, according to the Republican summary.

Bloomberg’s Alexander Ruoff contributed.

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