UPDATE 1-Obama: Now is not time to slow health overhaul

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WASHINGTON, July 17 (Reuters) - President Barack Obama, scrambling to regain the initiative on U.S. healthcare reform, insisted on Friday that "now is not the time to slow down" the effort to overhaul the troubled system.

Obama took his case to the American public as his far-reaching plan to guarantee healthcare coverage to all faced obstacles over its more than $1 trillion price tag and growing questions about how to pay for it.

"In the past few weeks we have forged a level of consensus (on healthcare reform) never before seen in this country," Obama said in an appearance at the White House.

Obama, who has urged Congress to finish healthcare legislation before starting its August recess, said he was "absolutely convinced" that the reform package would be passed this year.

Two committees of the House of Representatives on Friday passed bills aimed at overhauling the healthcare system.

But the head of the nonpartisan Congressional Budget Office caused a stir on Thursday when he said reforms being considered would do little to control rising costs.

"Now we've got to get over the finish line, and part of this process is figuring out how to pay for it," Obama said. (Editing by David Storey)