President Joe Biden lauded "uniquely accomplished" Ketanji Brown Jackson Friday as he nominated her to be the first Black woman in US history to serve on the Supreme Court.

Jackson was appointed to the federal bench in 2013, and was backed by three Republican senators last year when she was elevated to the DC Circuit Court of Appeals, seen as a staging ground for aspiring Supreme Court justices.

"She steps up to fill Justice (Stephen) Breyer's place on the court with a uniquely accomplished and wide ranging background," Biden said as he officially unveiled his decision at a White House appearance with the 51-year-old jurist.

"As it happens, I share a birthday with the first Black woman ever to be appointed as a federal judge, the Honorable Constance Baker Motley," Jackson said as she accepted the nomination.

"We were born exactly 49 years to the day apart. Today, I proudly stand on Judge Motley's shoulders, sharing not only her birthday, but also her steadfast and courageous commitment to equal justice under law."

With one liberal justice replacing another the announcement will not reshape the ideological make-up of the court -- but it is a huge moment for Biden personally and politically.

White House officials hope it will provide a few days of positive news coverage ahead of the president's State of the Union address on Tuesday.

The pick presents an opportunity for the administration to pivot from a spate of bad news in recent months, with Biden's domestic agenda stalled amid runaway inflation and plummeting poll numbers.

The announcement is a chance for Biden to show the Black voters who rescued his floundering 2020 primary campaign that he can deliver for them following the recent defeat of voting rights legislation.

"For too long, our government, our courts haven't looked like America," Biden said. "I believe it's time that we have a court reflects the full talents and greatness of our nation with a nominee of extraordinary qualifications, and that we inspire all young people to believe that they can one day serve their country at the highest level."

Black Americans are among Biden's strongest supporters, with two-thirds approving of his job performance, according to a CBS poll released last week.

His popularity among the key demographic however declined over the months following his inauguration and he has not recovered the lost ground.

In his first year in office, Biden nominated 62 women to the federal judiciary, including 24 Black women.

In this file photo taken on April 28, 2021, Ketanji Brown Jackson, then a nominee to be US Circuit Judge for the District of Columbia, testifies during her Senate Judiciary Committee confirmation hearing in Washington, DC
In this file photo taken on April 28, 2021, Ketanji Brown Jackson, then a nominee to be US Circuit Judge for the District of Columbia, testifies during her Senate Judiciary Committee confirmation hearing in Washington, DC POOL via AFP / Tom WILLIAMS

But there are still only a few dozen active Black female judges on the federal bench out of almost 800 total.

The president had promised during his successful 2020 White House run to nominate a Black woman to the Supreme Court for the first time in US history.

The pledge dismayed some Republicans who thought ruling out candidates of other backgrounds would further politicize the judiciary.

Dismissing the objections, Biden shortlisted a handful of top Black women to replace the retiring Breyer, including southern jurists J. Michelle Childs and Leandra Kruger.

Reflecting Washington's bitter political divisions, at least two top Republicans depicted his eventual nominee as the darling of what they called the American far left.

Lindsey Graham had argued that it was "about time" a Black woman sat on the bench but the senator went to bat for Childs, who is from his home state of South Carolina.

Graham was among the three Republicans who supported Jackson last year when she was nominated for the DC Circuit Court of Appeals.

But he complained Friday that her nomination for the higher court meant "the radical left has won President Biden over again."

Senate minority leader Mitch McConnell echoed Graham's objection, saying Jackson was "the favored choice of far-left dark-money groups that have spent years attacking the legitimacy and structure of the Court itself."

But neither said outright they would oppose Jackson's appointment.

Jackson will now go through weeks of hearings and meetings with senators before her nomination comes to the floor, likely in April.

Republicans cannot block a Supreme Court nomination as long as all 50 Senate Democrats stick together, but the comments by Graham and McConnell signal a bumpier confirmation process than had been expected.

But the party has shown little appetite for a fight, which they fear could backfire, and are trying to keep the focus on kitchen table issues such as spiraling fuel and food costs.