The U.S. Senate doesn't officially return to Washington until next week and the House gets back to work tomorrow, but closed door talks on pending health care legislation continue.

House and Senate negotiators are working to hammer out the differences between their two bills.

President Obama met, Monday, with labor union bosses who want to limit proposed tax hikes on high cost insurance plans.

Tax increases, whether illegal immigrants can buy into insurance plans and how to restrict tax dollars from funding abortions are some of the other remaining issues.