WASHINGTON (AP) – The White House says a new bipartisan Medicare proposal would cause the health care program for seniors to "wither on the vine."

Communications Director Dan Pfeiffer said Thursday the overhaul proposed by Wisconsin Rep. Paul Ryan, a Republican, and Oregon Democratic Sen. Ron Wyden "would end Medicare as we know it" by shifting costs to retirees.

The Wyden-Ryan plan would set up a competition between traditional Medicare and regulated private insurance plans. Seniors would get a fixed amount to spend on a health plan no matter which coverage they selected. The overall growth in Medicare spending would be limited.

Ryan and Wyden say they want to tone down the political rhetoric over the future of Medicare and start a real national dialogue. An earlier plan by Ryan sparked a backlash.

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