British development finance agency CDC Group plans to invest up to $4.5 billion across Africa over the next four years to boost ties with the continent, its chief executive told Reuters on Wednesday, as the country prepares to leave the European Union.

With Britain set to leave the world’s biggest trading bloc in March, government officials have been touring Africa, hoping to bolster ties with main economies such as Nigeria, South Africa and Kenya.

Nick O’Donohoe said CDC, which has invested nearly $400 million in Nigeria, had committed $25 million to a local private equity firm, Synergy, to support small and medium sized companies in Africa’s most populous nation.

CDC also provided a $100 million loan to Nigerian fertilizer company Indorama. O’Donohoe said the agency would like to invest more in infrastructure, power, manufacturing and agriculture.

“We are opening a new office to help originate more transactions in Nigeria,” O’Donohoe said.

CDC aims to open a regional office for West Africa in Nigeria’s commercial hub of Lagos early next year and establish a presence in Nairobi, while also expanding in Johannesburg and with representative offices in Abidjan and Cairo.

In August, British Prime Minister Theresa May visited Nigeria where she sought to build a new trading relationship and urged the West African nation to tap London’s financial expertise for its infrastructure projects.

“Part of the reason the prime minister came here was to try to focus people’s attention on the growth opportunity and the investment and trade opportunity in Nigeria and that, you can be cynical to say, that’s partly Brexit,” O’Donohoe said.

Earlier this year, Britain added the naira as a “preapproved” trade currency for Nigerian firms buying goods in Britain, while also exploring ways to list naira denominated bonds on the London Stock Exchange to help fund projects.

In April, Britain hosted a meeting of Commonwealth countries, including South Africa, Kenya and Nigeria, seeking to reinvigorate the network of mostly former colonies and drum up new trade among its members.

REUTERS