WASHINGTON — A Senate panel decided Wednesday to provide an additional 4,000 visas to allow Afghans who sided with the American-led coalition and are at risk of being killed or injured by the Taliban to resettle in the United States.

The Appropriations Committee voted unanimously, 30 to 0, to approve a foreign operations spending bill that includes a provision granting the extra visas and extending the so-called special immigrant visa program for another year.

The Afghan civilians worked for the coalition as interpreters, firefighters and construction laborers. But the militants considered them traitors. The top American commander in Afghanistan, Army Gen. John Nicholson, urged Congress to extend the special immigrant visa program so they and their families could escape what he called "grave consequences."

Sen. Jeanne Shaheen, D-N.H., pushed for the program to be continued, telling her colleagues that many Americans who served in Afghanistan are alive today because of the support they received from Afghans willing to put themselves in danger.

"If Congress fails to extend this program, this could be a death sentence for many Afghans who have stood shoulder-to-shoulder with our military and diplomats," Shaheen said.

Shaheen and Sen. John McCain of Arizona, the Republican chairman of the Senate Armed Services Committee, had sought earlier this month to extend and expand the visa program by adding an amendment to the annual defense policy bill. But a procedural dispute prevented most amendments from being debated and included in the legislation.

Senate backers of the visa program still face objections from skeptical lawmakers in the GOP-led House. In the House's version of the defense bill, lawmakers refused to provide the 4,000 additional visas. They did extend the program for a year, but restricted eligibility for visas only to Afghans whose jobs took them outside the confines of a military base or secured facility.

Congress has added 7,000 visas to the program over the last two years alone to meet the demand and the Obama administration requested 4,000 more for the fiscal year that begins Oct. 1. Since December 2014, the State Department has issued more than 3,000 special immigrant visas to Afghans who worked for the coalition. Thousands more visas are being processed through a pipeline that can take 270 days from start to finish.

Shaheen said the supply of visas could expire by end of the year unless more were approved.

The Congressional Budget Office has estimated the additional 4,000 visas would cost $446 million over the next 10 years. Afghans who resettle in the U.S. become lawful permanent residents and are entitled to federally supported benefits such as Medicaid, subsidies for health care and food stamps.

The cost has worried fiscal conservatives, who said it is not clear more visas are needed when so many haven't been used. The program's critics also said allowing so many Afghans to exit the country will drain Afghanistan of much needed talent.

Shaheen, a member of the Armed Services Committee, called objections over the cost a "red herring." The expenses are offset by cost-saving measures found elsewhere in the Defense Department budget, she said.