VA Secretary-designate Denis McDonough said Friday that his marching orders from President-elect Joe Biden were simple and direct: "to fight like hell for our veterans."

"Our men and women in uniform have had our country's back and when they come home we need to have their backs," said McDonough, 51, the former White House Chief of Staff and National Security Council chief of staff in the Obama administration.

If confirmed by the Senate to run the Department of Veterans Affairs, a $240 billion agency and the nation's largest health care system, McDonough said he would fight to give our veterans and their families the health care, respect and dignity they deserve."

He was introduced by Biden Friday at a Wilmington, Delaware, theater along with other Cabinet choices.

Among his top priorities, McDonough said, are "making our VA more welcoming to all veterans, including our women veterans, veterans of color and LGBTQ veterans," and "keeping faith with our incredible military families and caregivers."

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He also appeared to address concerns voiced by some in the veterans community and the VA unions that he lacked the military background and experience in health care they had expected in a nominee for the post.

"To the men and women of the VA, many of you veterans yourselves, to you and to the many dedicated veterans service organizations, I look forward to being your partner in delivering care and support second to none," McDonough said.

In his introduction, Biden said McDonough shared his belief that the government had many obligations, but only "one truly sacred obligation to prepare and equip our troops that we send into harm's way and then to care for them and their families when they return."

He called McDonough a "fierce advocate and a relentless workhorse, and ... a world-class manager with an innate understanding of how government can and must work for our veterans."

Biden also pledged that his administration would seek to boost the VA budget to attract more doctors, psychiatrists, and health care workers to the VA from the private sector to improve VA service.

In addition to McDonough, Biden also introduced former Iowa Gov. Tom Vilsack as his choice for Agriculture Secretary; Rep. Marcia Fudge for secretary of Housing and Urban Development; Katherine Tai for U.S. Trade Representative; and Susan Rice for head of the White House Domestic Policy Council.

"Some are familiar faces. Some are new in their roles. All are facing new circumstances and challenges. That's a good thing," Biden said.