U.S. President Barack Obama pauses during the 93rd annual American Legion National Convention in Minneapolis, August 30, 2011. Larry Downing/Reuters Anthem, one of the five biggest insurers in the US, is pulling out of the Obamacare insurance exchanges in Wisconsin and Indiana.

In an announcement Wednesday, the company said a combination of decreasing participation in the exchanges and political uncertainty made the company's presence in the two states no longer viable.

"Today, planning and pricing for ACA-compliant health plans has become increasingly difficult due to a shrinking and deteriorating individual market, as well as continual changes and uncertainty in federal operations, rules and guidance, including cost sharing reduction subsidies and the restoration of taxes on fully insured coverage," Anthem said in a statement provided to Business Insider.

Wisconsin and Indiana are the second and third states, respectively, from which Anthem has pulled out recently, following its decision to stop offering plans in Ohio earlier in June.

In comparison to Ohio, Anthem's exit from Indiana and Wisconsin will not leave any areas with no insurer, said Cynthia Cox, associate director at the Kaiser Family Foundation, a nonpartisan health policy think tank.

The insurer will continue to offer off-exchange individual health insurance plans in one county in Wisconsin and five counties in Indiana.

Anthem's statement follows a familiar pattern from other insurers who have announced large premium increases or exits from the markets. The statement notes not only the difficult participation circumstances in the market, but also uncertainty in Washington — like the potential discontinuation of cost-sharing reduction payments — that could be a serious blow to their bottom line.

Opponents of the Affordable Care Act were quick to pounce on the news, with Wisconsin Gov. Scott Walker, a Republican, releasing a statement just a few minutes after the news broke.

"Growing uncertainty in the health insurance market was created by Obamacare’s costly regulations and it is causing higher premiums and a lack of options," Walker said in a statement. "If we do nothing, more companies will back out and more people will lose coverage. Wisconsin families expect and deserve better health care coverage options and the time to act is now."

Anthem's statement also said the company was still working with regulators in other states to continue participation in their exchanges. Wednesday is the deadline for insurers to submit their intention to stay in exchanges in states that use the Healthcare.gov platform.

"Our commitment to members has always been to provide greater access to affordable, quality healthcare, and we will continue to advocate solutions that will stabilize the market and allow us return to a more robust presence in the future," Anthem said. "In those states where Anthem has not yet made a final participation decision, we continue to work with regulators and remain actively engaged in dialogue."