By Pavel Polityuk and Kiryl Sukhotski KIEV (Reuters) - Russian troops are strengthening their positions in eastern Ukraine and using aid shipments to smuggle in arms and other supplies to separatist forces, Kiev's military said on Tuesday. Military spokesman Andriy Lysenko said units of Russian troops had been identified in the big regional center of Donetsk, towns and villages to its east and in south-east areas near the Sea of Azov. Fifteen more Ukrainian servicemen were killed in fighting in the past 24 hours, Lysenko said. President Petro Poroshenko accused Russia on Monday of "direct and undisguised aggression" in Kiev's five-month war against pro-Russian separatists.
By Mark Trevelyan MOSCOW (Reuters) - Russia will update its military doctrine this year to take account of new threats including the Ukraine crisis, a Kremlin security aide said on Tuesday in forceful comments that highlighted a deepening Cold War-style standoff with NATO. Mikhail Popov, deputy head of the Kremlin's advisory Security Council, told RIA news agency that changes were being drafted in the light of risks connected with the Arab Spring, the Syrian civil war and the conflict between the Ukrainian government and pro-Russian separatists in Ukraine. The doctrine was last updated in 2010, when Russia identified NATO enlargement as a national threat and reaffirmed its right to use nuclear weapons if its existence was endangered. Back then, Popov said, "a number of top officials accused the leadership of our country of old thinking and declared that NATO is not Russia's enemy and will never attack Russia.