Britain has agreed to a deal with six southern African countries including South Africa, the continent's most developed economy, that will ensure continuity of trade conditions after Brexit, the British High Commission in South Africa said on Wednesday.

Political turmoil in the United Kingdom has generated uncertainty over how, when and even if the country will withdraw from the European Union. Its current exit date is set for Oct. 31.

But while the situation has left the future trade relationship between Britain and the EU in doubt, London has been working to minimise the impact of Brexit on other trading partners.

Britain initialled an Economic Partnership Agreement with the Southern African Customs Union (SACU) - comprising South Africa, Botswana, Lesotho, Namibia, and eSwatini (formerly known as Swaziland) - and Mozambique on Tuesday.

"This trade agreement, once it is signed and takes effect, will allow businesses to keep trading after Brexit without any additional barriers," Britain's International Trade Secretary Liz Truss said in a statement.

The agreement is still subject to final checks. But once signed formally, it will mirror the trade conditions the southern African nations currently enjoy with the EU.

Trade between Britain and the six countries was worth 9.7 billion pounds ($12 billion) last year, with machinery and motor vehicles topping British exports to the region. The UK meanwhile imported some 547 million pounds worth of edible fruit and nuts.

Britain has already signed trade continuity agreements with countries accounting for 89 billion pounds of its external trade.

Prime Minister Boris Johnson says Britain must leave the EU on Oct. 31, but parliament has passed a law compelling him to ask Brussels to delay Brexit until 2020 unless he can strike a divorce deal. Johnson says he will not request an extension. ($1 = 0.8095 pounds) (Reporting by Joe Bavier Editing by Gareth Jones)