President Joe Biden called Wednesday for a long-term partnership with Africa rooted in good governance as US businesses unveiled billions of dollars led by tech investment for a continent where China has become a top player.

Addressing a summit that brought 49 African leaders to the Washington cold, Biden avoided uttering China's name but made clear the United States would take a different approach.

At the first such gathering since Barack Obama invited African leaders in 2014, Biden said the United States sought "partnerships -- not to create political obligation, to foster dependence, but to spur shared success and opportunity."

"When Africa succeeds, the United States succeeds. Quite frankly, the whole world succeeds as well," the president said.

The Biden administration is laying out more than $55 billion in support over the three-day summit and on Wednesday welcomed US and African businesses, which promised more than $15 billion in trade deals.

In an implicit contrast with China, which takes a hands-off approach in countries where it invests, Biden highlighted "the core values that unite our people -- all our people, especially young people: freedom, opportunity, transparency, good governance."

Africa's economic transition, he said, "depends on good government, healthy populations and reliable and affordable energy."

Biden stayed uncharacteristically brief, saying leaders likely wanted to see the World Cup, and watched a semi-final with the prime minister of Morocco, the first African nation to advance so far in the football tournament.

Biden later invited the leaders to the White House to a dinner of sea bass and black-eyed peas and a performance by Gladys Knight.

In a toast, Biden spoke of the "unimaginable cruelty" of "my nation's original sin" -- the enslavement of Africans -- and hailed the contributions of the diaspora.

"Our people lie at the heart of the deep and profound connection that forever binds Africa and the United States together," Biden said.

- Pushing tech investment -

China in the past decade has surpassed the United States on investing in Africa via highly visible infrastructure projects, often funded through loans that have totaled more than $120 billion since the start of the century.

Defense Secretary Lloyd Austin on Tuesday warned African leaders that both China and Russia were "destabilizing" the continent, saying Beijing's mega-contracts lacked transparency.

Biden announced a $100 million aid package for clean energy and the White House unveiled another $800 million in public and private financing for digital development in Africa.

In one of the biggest corporate announcements, Visa said it would pump $1 billion into Africa to develop digital payments -- an area in which China has emerged as a global leader.

Cisco and partner Cybastion said they would commit $858 million to bolster cybersecurity through 10 contracts across Africa, addressing a key vulnerability, and the ADB Group promised $500 million starting in Ivory Coast for cloud technology centers that can draw major US firms.

Microsoft said it would employ satellites to bring internet access for the first time to some 10 million people, half of them in Africa, starting in Egypt, Senegal and Angola.

In Africa, "there is no shortage of talent, but there is a huge shortage of opportunity," Microsoft president Brad Smith told AFP.

- Putting standards on aid -

China denies US accusations it is imposing a "debt trap" in Africa and in turn has accused Washington of turning the continent into a geopolitical battlefield.

The United States has made much of its infrastructure aid conditional on democratic standards.

Biden announced that four nations -- Gambia, Mauritania, Senegal and Togo -- were selected to design future US grants through the Millennium Challenge Corporation, which funds projects in countries that meet key standards on good governance.

Secretary of State Antony Blinken took part in the signing of a $504 million infrastructure package through the corporation that will connect Benin's port of Cotonou with landlocked Niger's capital Niamey, with US officials estimating 1.6 million people will benefit.

"For a long time we've considered this to be our natural port," Niger's President Mohamed Bazoum said, as he promised "institutional reforms" to support trade.

Benin's President Patrice Talon thanked the United States for addressing development, saying: "The attractiveness of Africa must be a part of the relationship with the US."

Blinken said the deal will not "saddle governments with debt."

"Projects will bear the hallmarks of America's partnership," Blinken said. "They'll be transparent. They'll be high quality. They'll be accountable to the people that they mean to serve."