By Caren Bohan and Yasmeen Abutaleb
WASHINGTON (Reuters) - Republicans launched a fresh assault on "Obamacare" Wednesday, promising a congressional investigation after the White House delayed a requirement for employer-provided health insurance until after the 2014 congressional elections.
Criticism was not confined to Republicans. The AFL-CIO labor organization, a supporter of the health care law, issued a statement asking that its own requests for changes be given the same consideration the White House has extended to employers.
That raised the prospect of numerous interest groups seeking to reopen previously settled disputes over the 2010 law.
A brief White House response came from Deputy Press Secretary Josh Earnest, who said the delay "should inspire confidence." It "demonstrates our willingness to work with the business community."
The criticisms complicate White House efforts to convince millions of Americans to sign up for coverage under President Barack Obama's signature domestic policy initiative.
A committee of the Republican-controlled House of Representatives wrote top administration officials, including Treasury Secretary Jack Lew, demanding to know why lawmakers were not informed sooner that the administration was considering delaying a requirement for employer provided health insurance.
"Despite delays and missed deadlines, administration officials had repeatedly testified before Congress that they were still on schedule to implement the law," said Representative Fred Upton, chairman of the House Energy and Commerce Committee.
Whether the investigation sheds light on the decision, it promises to prolong negative publicity about the law less than six months before it is to be rolled out.
In postponing the employer mandate on Tuesday, Upton said in a statement, the administration "admitted that wasn't the case, and it's clear we have no idea the full scope of delays and disarray that may be coming."
Senator John Barrasso, a Wyoming Republican and leading critic of the health law, accused the administration of carrying out a "cynical ploy" with postponement of the employer mandate.
"The public already lacks confidence in the law and it seems that now the administration is finally admitting that this law is unworkable, unaffordable and continues to be very unpopular," Barrasso said.
Since Obama won reelection in 2012 after a campaign in which the health law was a major issue, Republicans have sought new ammunition to undermine Obamacare. Democrats have blocked more than 30 Republican efforts to repeal all or part of the law.
Among Obama's supporters, the AFL-CIO labor organization, a staunch ally of the Democratic president, said it found the decision to postpone employer provided coverage "troubling."
AFL-CIO President Richard Trumka complained that the White House showed willingness to provide flexibility for the business community while reluctant to make changes sought by labor.
He said he would press his concerns and hoped "the administration will address" them "just as they have the concerns voiced by employers."
(Additional reporting by Steve Holland and Roberta Rampton. Editing by Fred Barbash and David Gregorio)