Islamabad, Pakistan (CNN) -- Pakistan asked the British government to pull at least 18 military trainers from the country, British officials in Islamabad and London told CNN Monday.
The trainers were withdrawn from Balochistan and were not expelled, the Ministry of Defence said.
George Sherriff, a spokesman for the British High Commission in Islamabad, told CNN Pakistan had cited "security concerns" in its request. He said the British "understood" the concerns, but did not say what they were.
Pakistan asked the United States last month to reduce the number of military trainers it has in the country after the raid by U.S. Navy SEALs to kill Osama bin Laden.
A Pentagon spokesman said at the end of that the United States had begun to comply and is removing some of the more than 200 personnel who are posted there.
The British experts were assigned to train Pakistan's Frontier Corps, the paramilitary force that is taking on various militant groups along Pakistan's western border, the British High Commission said.
The team was asked to withdraw "in the last couple of weeks," the Ministry of Defence said.
The Defence Ministry said the request was to "withdraw some of its training support teams on a temporary basis.
"We are providing training support at the invitation of the Pakistan Government and welcome their advice on these matters. The training teams will continue their own training and will be ready to re-deploy at the first possible opportunity," the ministry said.
From CNN's Reza Sayah and Claudia Rebaza