The United States on Wednesday criticized what it described as Russia's "self-defeating" decision to pull out of a decade-old drug control agreement.
"We are seeking more clarification from the Russian government at the moment with regard to what they see this covering. We obviously regret this decision," State Department spokeswoman Victoria Nuland said.
The Russian government published a decree from Prime Minister Dmitry Medvedev saying Moscow had informed Washington it was withdrawing because the deal "does not address today's realities and has exhausted its potential."
Moscow said it lacked the money to fight drugs when it struck the deal in September 2002 at a time of warming relations that followed the September 11, 2001 attacks on the United States.
The statement implied that Russia -- whose economy grew in the past 10 years on the back of high global energy prices -- was now sufficiently rich to tackle the fight against drugs on its own.
Nuland said the decision to end the program which had committed some $2 million for law enforcement training had come out of the blue, and Washington had only been informed of its this week.
It is the third bilateral accord ripped up by Moscow in recent months -- after the Russian government shut down the USAID aid agency offices last year and also banned adoptions of Russian children by US families.
"I think from our perspective, this is also self-defeating because most of the work we were doing under this agreement was also involved in training Russians, training them on trafficking in persons, interdiction, training them on implementation of the mutual legal assistance treaty that we have," Nuland told journalists.
Washington and Moscow have a "range of challenging issues," she acknowledged.
"But that doesn't change the fact that when we do work together, when we can cooperate, whether it's bilaterally or whether it's in the international realm, it helps both of us, and it's in our mutual interest."