In the waning days of his presidency, US President Joe Biden made a rare visit to Angola, touting support for Africa and a key railway project. With his term ending soon, experts question whether these promises will be fully delivered.

Biden had promised to visit sub-Saharan Africa last year after reviving the US-Africa Leaders Summit in 2022. His trip, the first by a US president to the region since Barack Obama in 2015, was delayed until October and then postponed further because of Hurricane Milton.

"Biden's visit to Angola in the final month of his presidency raises concerns among African countries about the US' strategic priorities and the sustainability of its Africa policy," said Li Yincai, an associate researcher of African studies at the Shanghai Academy of Social Sciences.

A major focus of Biden's trip is the Lobito Corridor, a railway linking Zambia, the Democratic Republic of Congo and Angola. It aims to help transport critical minerals from the inland countries to the Atlantic via Angola's Lobito port.

It will cut transport time from 45 days to 45 hours, according to the US administration. Part of the project's objectives is to strengthen the US presence in a region rich in metals and raw materials crucial to the production of electric vehicle batteries.

"The trip is a promise Biden must fulfill, especially against the backdrop of major country competition," Li said. "The so-called critical minerals play a significant role in this move. Biden hopes to achieve some tangible results before his presidency ends."

Chen Zheng, a lecturer on US politics at Beijing Foreign Studies University and a researcher at the Beijing-based think tank Taihe Institute, echoed these views, saying African American votes are a key support base for the Democratic Party.

Key voting bloc

In the global arena, the United States needs to maintain friendly relations with African countries as Africa is a key voting bloc for issues concerning global governance, she said.

On Wednesday, Biden announced another $600 million for the 1,300-kilometer Lobito Corridor, bringing the US investment in the project to more than $4 billion, as part of an international financing exceeding $6 billion, the White House said.

"Despite the renewed investment commitment, the area lacks key infrastructure, including logistics and industrial facilities, which casts a shadow over the US' ambitious plans," Chen said, adding that past US promises have often fallen short of delivery.

White House national security spokesman John Kirby said completing the Lobito Corridor will "take years", with much of the project likely falling to Biden's successor, Donald Trump, who takes office on Jan 20.

Li of the Shanghai Academy of Social Sciences said that while it is unclear whether Trump will continue Biden's legacy, he is expected to support parts of the Lobito project and maintain a close partnership with Angola for critical minerals.

During his visit on Tuesday to Angola's National Slavery Museum near the capital, Luanda, Biden said the US was "all in on Africa", pledging $1 billion of "new humanitarian support for Africans displaced from homes by historic droughts".

Li said: "Historically, US humanitarian aid often comes with political conditions or stipulations. While the main goal is to address crises like natural disasters or health emergencies, aid can also be linked to political, economic, or security objectives."

At the museum, which displays items from the trans-Atlantic slave trade, Biden acknowledged slavery as "our nation's original sin, one that haunted America".

"The history of slavery, along with the long impact of Western colonization in Africa, continues to evoke strong negative sentiments among African people," Chen said.

Agencies contributed to this story.