The commitment to Nato’s mission in Afghanistan will take the total number of UK troops in the country to 1100.
Around half of the troops will deploy from the Welsh Guards in August and the remainder will follow by February 2019.
They will help “bring the stability and security that the Afghan people deserve,” UK Prime Minister, Theresa May said.
The announcement comes a day before the start a potentially contentious NATO summit in Brussels on July 11, with U.S. President Donald Trump demanding that members contribute more to the alliance’s efforts and their own national defense.
Trump has called on allies to send reinforcements to Afghanistan to help deal with the security situation the country, where a NATO-led mission is assisting the Western-backed government in Kabul.
“In committing additional troops to the Train Advise Assist operation in Afghanistan, we have underlined once again that when NATO calls, the U.K. is among the first to answer,” May said.
The increase in British forces comes ahead of parliamentary elections in Afghanistan on October.