President Hamid Karzai of Afghanistan has sharply criticised the presence of Russian agents at a drugs raid on Thursday close to the border with Pakistan.
American and Russian officials say four drug processing laboratories in Nangarhar province were destroyed in their first co-ordinated operation in Afghanistan.
More than a tonne of heroin and opium was seized during the raids.
The head of Russia's drug control agency said it had a street value of $US250 million and was believed to have been destined for Central Asia.
Mr Karzai says the operation took place without the permission of his Government.
The BBC reports the presence of Russians is a sensitive issue in Afghanistan because of the Soviet intervention there 30 years ago.