President Barack Obama and Congressional leaders agreed on a key tax provision in the health care legislation debate a day after they met for several hours to work on merging the Senate and House versions of reform into a single bill that would provide insurance coverage to millions of Americans.

The major difference between the Senate and House versions of the legislation is over how the plan to insure more than 30 million Americans will be financed.

The Senate legislation would impose a new excise tax, nicknamed the "Cadillac tax," on expensive health plans sponsored by employers, which is supported by President Obama. The House version, supported by labor union leaders, would institute a new tax based on earnings.

Under the agreement reached Thursday, labor leaders will not oppose the Cadillac tax but will seek other concessions as the bills are merged, according to published reports.

President Obama released a joint statement Wednesday, with House Speaker Nancy Pelosi (D-Calif.) and Senate Leader Harry Reid (D-Nev.), saying they had made progress in bridging differences in the legislation.

Democratic leaders are looking for a swift final vote on the health care legislation to allow other top issues, such as job creation and immigration reform, to get greater attention.