US President Joe Biden has said he is "very proud to be the first American president visiting Angola" at the start of talks with his counterpart João Lourenço.

Discussions at the presidential palace in the capital, Luanda, were on security and trade.

The US government is backing a new 1,300km (810-mile) railway project linking an Angolan port with mining areas in neighbouring Democratic Republic of Congo and Zambia.

The visit to oil-rich Angola is part of a US effort to focus more on trade and investment in Africa, in what some analysts see as a counter to China's influence on the continent.

In his first and only trip to Africa during his presidency, Biden's choice of Angola is significant and it signals a dramatic improvement in relations between the two nations.

Welcoming the US president to the country, Lourenço said the visit "marks an important turning point in our relationship, which will undoubtedly gain a new dynamic from today onward".

"I'm deeply proud of everything we have done together to transform our partnership thus far," Biden said in response.

"You've heard me say it before... the United States is all in on Africa... The future of the world is here, in Africa, and Angola," the president said recalling remarks he made at the US-Africa summit in Washington in 2022.

Angola was firmly in the political orbit of China and Russia after independence from Portuguese colonial rule in 1975, but since taking power in 2017, Lourenço has steered it towards closer relations with the US.

Later on Tuesday Biden is due to visit a slavery museum. More than four million slaves were forcibly sent from this region of Africa to the Americas.

"Together, the United States and Angola acknowledge the past horrors of slavery and its legacy, while looking forward to a bright future of continually deepening collaboration between our nations," the White House said in a statement on Monday.