Defence officials say the emails did not contain information that could compromise operational security.
The Ministry of Defence has launched an investigation after emails containing classified information were sent to a close ally of Russia in a typing error.
The emails were intended for the US military, which uses the domain name “.mil”.
But they missed out the letter i, and so the messages went instead to the West African nation of Mali.
The MoD said fewer than 20 emails were sent to an “incorrect domain” and were “not classified at secret or above”.
In a tweet, it said it was “confident there was no breach of operational security or disclosure of technical data”, calling the emails “routine”.
“We have opened an investigation after a small number of emails were mistakenly forwarded to an incorrect email domain,” an MoD spokesman told PA news agency.
The spokesman added that all sensitive information used by the government department was “shared on systems designed to minimise the risk of misdirection”.
“The MoD constantly reviews its processes and is currently undertaking a programme of work to improve information management, data loss prevention, and the control of sensitive information,” they added.
Earlier this month, it emerged that millions of US military emails had also been sent to Mali, because of the same typing error.
Some of those emails were believed to have contained sensitive information including passwords, medical records and the itineraries of top officers.
Mali was one of the six African countries promised free grain shipments by Russian President Vladimir Putin after the collapse of the Black Sea deal with Ukraine earlier this month.
Russia’s navy blockaded Ukraine’s Black Sea ports following its invasion in February 2022, trapping 20 million tonnes of grain which were meant for export and creating food shortages in Middle Eastern and African countries.
Mali is also a close Russian ally because Moscow’s Wagner mercenaries have been deployed in the country to fight alongside the army against jihadists.
Earlier this week, US Secretary of State Antony Blinken said Mali’s defence minister, air force chief and the deputy chief of staff would be sanctioned for co-ordinating the spread of Wagner in the West African country.