WASHINGTON - Lawmakers have just one week left to overcome a congressional budget battle and avert a government shutdown.

The main point of discord is President Barack Obama's health care law, known as Obamacare, which is set to take effect on Oct. 1. Republicans in the House voted Friday to defund the law, vowing that they will not authorize the government to spend money unless it's off the table.

However, the Democratic-led Senate is refusing to budge on its support for Obamacare, and is certain to reject the House's spending plan when it votes this week.

A shutdown could mean that government agencies would be under staffed, and some employees could face an unpaid furlough from their jobs. That could cause delays in new filings for programs such as Medicare, veterans benefits and student loans.

The deadline to reach an agreement is Sept. 30.