President Barack Obama on Thursday signed into law a measure designed to keep funding for veterans' medical care steady amid future budget negotiations.

Noting the Veterans Affairs Department is providing care for veterans without a Congress-approved budget right now, Obama said the new law would guarantee timely and predictable funding by laying out the VA budget ahead of schedule. The president said the measure would let the VA know as much as a year ahead of time just how many tax dollars officials could expect to buy equipment, provide health care and hire employees.

"Over the past two decades, the VA budget has been late almost every year, often by months," Obama said in the White House's East Room, surrounded by veterans and lawmakers. "At this very moment, the VA is operating without a budget, making it harder for VA medical centers and clinics to deliver the care our vets need."

The White House said changing the funding process was needed to protect veterans' programs, given that Congress has been late 20 of the last 23 years in passing a budget bill. Aides say the uncertainty of the budget process harms those who have served in uniform because of financial uncertainty for programs.

"This is inexcusable. This is unacceptable," Obama said.

The VA provides health care for more than 23 million American veterans; as many as a quarter of the nation's population qualifies for VA coverage, either as veterans or family members of veterans. But the budget uncertainties have led to delays in replacing medical equipment or insufficient staff to handle their work.

Obama said the funding stability will help veterans receive the care they deserve.

"It ensures that veterans' health care will no longer be held hostage to the annual budget battles in Washington," he said.