WASHINGTON - Weary after a year of partisan bickering, lawmakers reached a tentative agreement Monday on a spending bill of more than $1 trillion that chips away at military and environmental spending but denies conservatives many of the policy changes they wanted on social issues, government regulations, and health care.

Environmentalists succeeded in stopping industry forces from blocking new clean-air regulations and a new clean-water regulation that mountaintop-removal mining interests opposed. But anti-Castro lawmakers appeared likely to win concessions that would weaken administration efforts to ease restrictions on Cuban immigrants on travel to the island and sending cash to family there.

The measure implements this summer's hard-fought budget pact between President Obama and Republican leaders. That deal essentially freezes agency budgets, on average, at levels for the recently completed budget year that were approved in April.

Drafted behind closed doors, the proposed bill would pay for the war in Afghanistan but give the Pentagon just a 1 percent boost in annual spending. The Environmental Protection Agency's budget would be cut 3.5 percent.

The bill also covers everything from money to combat AIDS and famine in Africa to budget increases for veterans' health care.

House Appropriations Committee Chairman Harold Rogers (R., Ky.) said bargainers had struck an agreement but would not formally announce it until Tuesday. A House vote is expected Thursday, and the Senate is likely to follow in time to meet a midnight Friday deadline before a stopgap funding measure expires.

The generally smooth negotiations on the omnibus spending bill contrasts with the partisan brawl over Obama's demand that Congress extend jobless benefits and a cut in the Social Security payroll tax. The House is set to vote on a GOP-friendly version of the payroll-tax cut Tuesday; negotiations with the Democratic-controlled Senate on a compromise measure have yet to begin. House Speaker John Boehner predicted the House would approve legislation that extends the payroll-tax cut but curtails extra benefits for the long-term unemployed.

The spending measure, meanwhile, is likely to meet resistance among tea-party conservatives, many of whom believe the August budget and debt compromise did not cut enough.

Conservative ire is likely to be magnified once the negotiating outcome regarding dozens of GOP policy "riders" is made final. House Republicans larded the measures with provisions aimed at rolling back EPA rules, such as regulations on coal ash.

The most controversial riders, lawmakers said, were dumped because of opposition from Obama and Democrats controlling the Senate. But Democrats realize they must show flexibility to win GOP votes in the House. That means Democrats are likely to accept, reluctantly, a rider that blocks the city of Washington from funding abortions for poor women.

Besides the cut in EPA funding, foreign-aid spending also would drop, and House lawmakers would absorb a 6 percent cut to their office budgets.

House GOP leaders pressed riders to block the Obama administration's 2009 policy lifting restrictions on travel and money transfers by Cuban-Americans to families remaining in Cuba, and some Democrats backing the administration policy seemed resigned to defeat.

On spending, the measure generally consists of relatively small adjustments to thousands of individual programs. Agencies such as the Border Patrol and Immigration and Customs Enforcement will get a boost within the Department of Homeland Security, while GOP defense hawks won additional funding to modernize the U.S. nuclear-weapons arsenal. The troubled, overbudget next-generation F-35 fighter plane program would be largely protected.

Democrats won a modest increase in funding for schools with large numbers of disadvantaged students.