WASHINGTON -- Senate Democrats unveiled legislation Tuesday providing $6 billion in new disaster aid to help victims of Hurricane Irene and past disasters dating to Hurricane Katrina.

A Senate Appropriations subcommittee responsible for the Federal Emergency Management Agency's budget approved the measure by voice vote.

At the same time, the measure's author said that with FEMA's disaster aid coffers running dangerously low, it may be necessary to add additional, more immediate disaster aid to a stopgap funding bill that's expected to be enacted before the FEMA funding measure.

The moves in the Democratic- controlled body could spark a battle with tea party-backed House Republicans, who say that Congress should cut federal spending elsewhere to pay for disaster aid.

The $6 billion in disaster relief is for the budget year beginning Oct. 1 and is $4.2 billion above President Barack Obama's February request of $1.8 billion, which has been criticized by Democrats and Republicans for being too little to help states rebuild from past disasters like hurricanes Katrina, Rita and Gustav and the massive Tennessee floods of last spring, as well as for Joplin, Mo., and the Alabama towns devastated by tornadoes last spring.

The $4.2 billion would be added above spending "caps" set under last month's budget deal. None of the handful of Republicans present at Tuesday's Senate Appropriations panel vote complained about the move.

Sen. Mary Landrieu, D-La., the panel's chairman, said that a more pressing matter was an immediate shortfall in FEMA's disaster relief fund, which was already running low before Irene walloped the East Coast .