The US Senate unanimously confirmed a former army officer and corporate leader as secretary of veterans affairs Tuesday, as lawmakers acknowledged he faces an uphill battle to reform the scandal-plagued department.

Lawmakers closed ranks, 97-0, to approve President Barack Obama's nominee, former Procter & Gamble chief executive Robert McDonald, as head of the Department of Veterans Affairs.

They were keen to fill the void after VA secretary Eric Shinseki resigned amid a string of crises over failures in health care for America's retired warriors.

Obama hailed the bipartisan support for McDonald, a man he described as "deeply committed" to serving US veterans.

"As a country, we have a solemn duty to serve our veterans as well as they have served us," Obama said in a statement.

"I know Bob will help us honor that commitment and make sure every veteran gets the care they deserve, the benefits they've earned, and the chance to pursue the American Dream they've risked so much to protect."

In May, an inspector general found that 1,700 veterans in the Phoenix area alone had been kept off the main waiting list for primary care. Up to 40 patients are said to have died while waiting for treatment.

An internal review concluded that delays and other management failures in care were systemic and nationwide.

Democratic Senator Patty Murray warned that McDonald faces "a truly monumental task" of reforming the agency responsible for treating millions of veterans.

Senate Republican Richard Shelby said McDonald's confirmation should bring "renewed commitment, energy and acumen to address the system problems that we all know exist."

Lawmakers are seeking a legislative fix, and on Monday congressional negotiators agreed on a plan to help veterans get care at non-VA medical providers if wait times at VA hospitals are too long.

The House and Senate could vote on the measure this week before lawmakers leave for August recess.