Congressional leaders announced this morning they would unveil new legislation to extend through the end of 2010 various tax incentives for charitable donations, including gifts made by older people from individual retirement accounts.

The bill would also ease rules governing employer contributions to defined-benefit pension plans, a move that would offer relief to charities whose plans have suffered investment losses during the economic downturn.

Those measures will be included in the American Jobs and Closing Tax Loopholes Act, H.R. 4213, a package of wide-ranging proposals in areas including unemployment insurance and health benefits, small-business loan programs, aid to states, tax cuts, Medicare payments, disaster relief, and mine safety.

Both the House and Senate have previously agreed to extend the charitable incentives, but the two sides have been wrangling over how to merge the two bills and how to pay for the overall legislation. Rep. Sander Levin, the Michigan Democrat who chairs the House Ways and Means Committee, and Sen. Max Baucus, the Montana Democrat who chairs the Senate Finance Committee, released a summary of the new bill this morning.

It would allow people age 70 1⁄2 and older to continue giving up to $100,000 a year from their individual retirement accounts to charity without having to pay taxes on the distribution. It would also extend tax provisions to encourage donations of property, food inventory, books to public schools, and computer equipment for educational purposes.

The pension measure would give employers that operate defined-benefit plans — which provide specific amounts of money to retired employees — more time to repay the losses suffered by the plans during the 2008 stock-market crash.

Representative Levin has said congressional leaders aim to get the legislation passed before lawmakers take their Memorial Day recess.