WASHINGTON — Responding to pressure from Congress and veterans groups, the Department of Veterans Affairs is relaxing a rule that makes it hard for some veterans in rural areas to prove they live at least 40 miles from a VA health site.

The change comes amid complaints from lawmakers and advocates who say the VA’s current policy has prevented thousands of veterans from taking advantage of a new law intended to allow veterans in remote areas to gain access to federally paid medical care from local doctors.

The VA said it will now measure the 40-mile trip by driving miles as calculated by Google maps or other sites, rather than as the crow flies, as currently interpreted. The rule change is expected to roughly double the number of eligible veterans.

“We’ve determined that changing the distance calculation will help ensure more veterans have access to care when and where they want it,” Veterans Affairs Secretary Robert McDonald said in a statement. The change will be unveiled at a hearing Tuesday before the Senate Veterans Affairs Committee.

The committee’s chairman, Sen. Johnny Isakson, R-Ga., and other lawmakers have criticized the VA for what they call an overly strict interpretation of a landmark law adopted last year to overhaul the VA and make it easier for veterans to get private care paid for by the government. The law was passed in response to a scandal over long wait times for veterans seeking health care.

“Given the clear intent of Congress to reduce barriers to care, it is perplexing that the VA is not using its authority to allow non-VA care for those who face a geographic challenge in accessing care, including long drive times or health conditions that make travel difficult,” 42 senators from both parties wrote last month in a letter to McDonald.