Two unions representing federal employees are asking House members to vote against a proposal that would require federal employees to contribute more toward their retirement benefits.

Separate letters from the legislative director of the American Federation of Government Employees and the president of the National Treasury Employees Union argue that federal employees are being targeted disproportionately in the budget process.

The legislation, compiled and passed by the House Budget Committee Monday based on earlier recommendations from other House committees, seeks to avert automatic “sequestration” cuts from many government programs set to go off next year, by finding more than $300 billion in savings.

The proposal would cut $79 billion over 10 years from federal retirement programs, wrote Beth Moten, AFGE’s director for legislative and political affairs, in a letter sent to all House members.

Under the proposal, which the House is scheduled to consider Thursday, federal employees would have to contribute an additional 1.5 percent of their salary in 2013, another 0.5 percent in 2014 and 1 percent more each year between 2015 and 2017. The increases would affect employees enrolled in the Federal Employees Retirement System and the Civil Service Retirement System.

Currently, CSRS-enrolled employees contribute 7 percent to their federal retirement defined benefit plan, while FERS-enrolled employees contribute 0.8 percent and also pay the Social Security tax, typically 6.2 percent but 4.2 percent this year. But under the plan, by 2017, CSRS employees would contribute 12 percent of their salary toward their defined benefit and FERS-enrolled employees 5.8 percent toward theirs, plus Social Security.

Moten noted the increase would include no increase in retirement payouts.

“AFGE strongly opposes the Republican Sequester Replacement Reconciliation Act of 2012 which would drastically increase taxes on federal employees for their retirement benefits, and make appalling cuts to other federal programs which provide a safety net for our country’s most vulnerable populations,” Moten wrote.

“Make no mistake about it; an increased contribution toward one’s pension, with no corresponding increase in benefits, is a pay cut,” NTEU President Colleen M. Kelley said in her letter, also sent to all House members. “A pay cut of this magnitude simply cannot be defended, especially when there has been no pay raise for the last two years.”

Read Moten’s letter below: