MOSCOW (Reuters) - Russian President Vladimir Putin on Tuesday urged the opposing sides in the Nagorno-Karabakh conflict to hold their fire, during a conversation with Armenian Prime Minister Nikol Pashinyan, the Kremlin said in a statement. Putin emphasised the urgent need for a ceasefire and for all sides to take measures to de-escalate the crisis, the Kremlin said. Armenia and Azerbaijan accused one another on Tuesday of firing directly into each other’s territory and rejected pressure to hold peace talks as their conflict over the enclave of Nagorno-Karabakh threatened to spill over into all-out war. Reporting by Polina Devitt and Darya Korsunskaya; Writing by Alexander Marrow; Editing by Mark Trevelyan