The exploits of Paris Davis, now 83, were largely forgotten by a US military bureaucracy that failed to process his paperwork, effectively denying him the Medal of Honor, the country's highest military distinction.

Davis is "a true hero of the nation," Biden said at a White House ceremony.

Biden said that the now retired Green Beret colonel had grown up in a racially segregated US South, where "in the eyes of the law he was less than a person."

Despite the challenges, Davis was among the first Black Special Forces officers after he overcame efforts to dissuade him from fighting among the US army's elite, Biden said.

"But Paris didn't listen to them, and thank God he didn't," the president said, describing in detail how Davis saved two of his countrymen from a Viet Cong ambush in the early days of the war.

In June 1965, Davis and the three Green Berets under his command were pinned down by relentless enemy fire as they returned from a raid.

Heavily outnumbered, Davis, who was 26 at the time, braved the enemy to rescue his fellow soldiers, who nominated him for the Medal of Honor immediately following the battle.

Invoking the long delay between his acts of bravery and the Medal of Honor, one of the battle's veterans wondered, in an interview with the New York Times, if Davis had been a victim of racial discrimination.

Davis told CNN on Thursday that he wasn't "going to spend 50 years thinking" about the medal that never was.

The "country has been pretty damn good to me," he said.

After leaving the army in 1985, Davis started a small newspaper in the US state of Virginia.