In his first extensive remarks since the confrontation at sea on Sunday, Putin said it had been orchestrated by Kiev as a “provocation”.
He said the Ukrainian ships had entered Russian territorial waters and refused to respond to requests to stop from Russian patrol boats.
“What were they Russian forces supposed to do” Putin said when asked about the incident at an international investment forum in Moscow.
“They were fulfilling their military duty. They were fulfilling their lawful functions in protecting Russia s borders. They would do the same in your country.”
Moscow and Kiev have traded angry accusations since Russian navy vessels fired on, boarded and captured the three Ukrainian ships off the coast of Crimea.
After warning of the threat of “full-scale war”, Ukrainian President Petro Poroshenko on Wednesday signed an act imposing martial law for 30 days in regions bordering Russia, the Black Sea and the Sea of Azo