Two of the central promises of President Barack Obama's health care overhaul law are unlikely to be fulfilled, Medicare's independent economic expert told Congress on Wednesday.

The landmark legislation probably won't hold costs down, and it won't let everybody keep their current health insurance if they like it, Chief Actuary Richard Foster told the House Budget Committee. His office is responsible for independent long-range cost estimates.

Foster's assessment came a day after Obama in his State of the Union message told lawmakers that he's open to improvements in the law, but unwilling to rehash the health care debate of the past two years. Republicans want to repeal the landmark legislation that provides coverage to more than 30 million people now uninsured, but lack the votes.

Foster was asked by Rep. Tom McClintock, R-Calif., for a simple true or false response on two of the main assertions made by supporters of the law: that it will bring down unsustainable medical costs and will let people keep their current health insurance if they like it.