MOSCOW - Russia said on Friday that US sanctions imposed over the annexation of Crimea would not serve American interests and would elicit a tough response, harming bilateral ties. 'We ... will be tough in our response,' the Russian Foreign Ministry said in a statement. 'Washington should be under no illusions: The effectiveness of its sanctions in terms of American interests is zero. But the harm to US-Russian relations due to these irresponsible actions is inevitable.'