Washington ( CNN ) -- Union leaders , the White House and congressional Democrats have agreed to limit the reach of a tax on high-end health insurance plans that would help pay for a proposed overhaul of the U.S. health care system , union leaders involved in the talks said Thursday . The proposed thresholds for taxing health plans will be raised from $ 23,000 to $ 24,000 for families and from $ 8,500 to $ 8,900 for individuals , AFL-CIO President Richard Trumka told reporters . Dental and vision benefits wo n't be counted toward that amount after 2014 , he said . Health plans covered by union contracts would not be subject to the 40 percent tax until 2018 -- a transition period union leaders said is comparable to those offered to other private insurers . The threshold for taxing other plans will be adjusted by 1 percent above the annual rate of inflation , and plans involving large numbers of women or the elderly will get breaks as well , Trumka said . The changes will reduce the $ 150 billion expected to be raised over 10 years by about $ 60 billion , he said . And union plans would be able to enter the health care exchanges set up under the bill in 2017 , he said . The tax on what have been dubbed `` Cadillac '' health care plans is a key feature of the Senate health care bill , but it has drawn opposition from Democrats in the House of Representatives and from unions . President Obama , who has made health care his top priority in Congress , supports the excise tax as a way to contain the rise of health-care costs . Trumka and other top union officials have held a series of talks at the White House for the past three days as congressional negotiators tried to merge the two bills together . He warned earlier this week that congressional Democratic candidates could risk losing labor 's support if the final bill included a tax on high-cost health plans . But he said that despite all-but-total Republican opposition in both houses of Congress , supporters of health care reform stood `` on the threshold of a milestone . '' `` We do n't look at this as the end of our fight for real reform , but another step along the way in the quest for real reform , '' Trumka said . Labor leaders said the changes they negotiated would help not only union members , who make up about 12 percent of the U.S. work force , but all working families . But Don Stewart , a spokesman for Senate Republican leader Mitch McConnell , dismissed the plan as `` a sweetheart deal . '' `` Americans are overwhelmingly opposed to this bill , '' he said . `` Another sweetheart deal is n't going to turn that around . '' A CNN/Opinion Research Corp. poll released Thursday found much stronger support for the financing plan in the House bill , which would impose a 5.4 percent income tax surcharge on incomes higher than $ 500,000 for individuals or $ 1 million for couples . The survey found 61 percent of the public favors the House provision , while the Senate bill drew 29 percent support . Trumka told reporters that leading Democrats were behind the compromise . But House Speaker Nancy Pelosi , D-California , said she had not seen anything in writing Thursday evening . Rep. Joe Courtney , D-Connecticut , a leading opponent of the excise tax , said the proposal was more fair than the current Senate bill . `` However , the devil is in the details , and I will reserve judgment on any compromise until I have had the time to review the proposal , '' he said in a written statement . Obama did not directly address the plan as he addressed reporters ahead of a House Democratic Caucus meeting Thursday night . But he dared Republicans to run in the November midterm elections on a platform of rolling back `` something that Washington has been talking about since Teddy Roosevelt was president . '' `` If Republicans want to campaign against what we 've done by standing up for the status quo and for insurance companies over American families and businesses , that is a fight I want to have . If their best idea is to return to the bad policies and the bad ideas of yesterday , they are going to lose that argument . '' Democratic negotiators planned to return to the White House late Thursday . A senior leadership aide said Democratic leaders and White House officials want to send the bulk of the health care package to the nonpartisan Congressional Budget Office for a cost estimate soon -- even as soon as the end of this week . The aide said the controversial issues of abortion and immigration are not likely to be resolved by then , but because they would have no impact on the cost of the bill , negotiators could work out those details separately . House Majority Leader Steny Hoyer , D-Maryland , said negotiators are working to get agreement on the overall health care package by the end of this week . `` That 's been the goal . But it 's a goal , it 's not a deadline , '' Hoyer said . CNN 's Dana Bash , Deirdre Walsh , Ted Barrett , Lisa Desjardins and Matt Smith contributed to this report .
AFL-CIO chief says threshold for taxing high-end health insurance plans will rise . Dental , vision benefits wo n't be counted toward that amount after 10 years , he says . He says $ 60 billion expected to be raised over 2010 to be cut by $ 150 billion . Obama challenges Republican to run in 2010 against changes to health system .