The Prime Minister arrived in Johannesburg, South Africa to meet world leaders at the annual G20 summit.
The summit brings together the 20 largest economies, although Donald Trump decided not to attend due to widely discredited claims that white people are being persecuted in the country.
Sir Keir Starmer, whose critics call him “Never Here Keir” due to the frequency of his international travel, will highlight the benefits of the prime minister acting as an ambassador for British businesses abroad.
Before the official opening of the summit, Sir Keir will visit Johannesburg depots to see trains built at Derby and announce a new agreement under which the UK will “provide strategic advice and advisory services” to South African railways.
The work will be carried out by Crossrail International, owned by the UK government.
It also signed an agreement with Vietnam to provide similar services there.
Downing Street says Africa offers what it calls “unprecedented future opportunities for British business”, given that half of Africans are under 20 and more than a quarter of the world's population will live in Africa by 2050.
“I will focus on the deals we can do, the business we can do with our partner countries and make sure that the work we do internationally has a direct impact on our country,” he told reporters on a flight to South Africa.
“If you want to tackle the cost of living challenge and improve people's well-being by creating good and secure jobs, investment from G20 partners and allies is really important,” he added.
Trump will skip the summit, declaring it an “utter disgrace” in a social media post and repeating his claim that white Afrikaners are being persecuted in South Africa.
The Trump administration has offered refugee status to white South Africans in the United States. currently take precedence over ethnic groups.
South African President Cyril Ramaphosa said US absence from G20 was 'their loss' and added that “the boycott policy does not work.”
None of South Africa's political parties – including those representing Afrikaners and the white community as a whole – declared that genocide was taking place in South Africa.
