WASHINGTON — President Obama, citing a new White House study suggesting that small businesses pay far more per employee for health insurance than big companies, said yesterday the disparity is "unsustainable — it's unacceptable."

"And it's going to change when I sign health insurance reform into law," the president said in his weekly Internet and radio address.

A new study by the White House Council of Economic Advisers said small businesses pay up to 18 percent more to provide health insurance for their employees.

It was released yesterday as part of the administration's aggressive campaign to build public and congressional support for Obama's health care efforts.

Obama had called for Congress to vote on health legislation by the August recess.

He now says he expects a bill by year-end.

Republicans dismissed the new report as more political propaganda by the administration.

"There's a reason why almost every employer and small-business group is opposed to the Democrats' government takeover of health care, and that's because it would impose new job-killing taxes during a recession," said House Minority Leader John Boehner, R-Ohio. "No report can change that."

And in the weekly GOP address, Rep. Cathy McMorris Rodgers of Washington state, vice chair of the House Republican Conference, said, "America's small businesses will pay a high price." Citing a study by the National Federation of Independent Business, she said Democratic-written proposals would destroy a million more jobs than the economy has already lost.

She called the Democratic efforts "a prescription for disaster — one that will put Washington bureaucrats in charge of your family's personal medical decision."