By Humeyra Pamuk, Steve Holland and Dmitry Antonov WASHINGTON/MOSCOW (Reuters) -Western leaders stepped up preparations for any Russian military action in Ukraine on Tuesday, with the United States focusing on how to protect energy supplies and Britain urging other European nations to get economic sanctions ready. Tensions remained high after NATO said https://www.reuters.com/world/europe/nato-sends-ships-jets-eastern-europe-ukraine-crisis-2022-01-24 on Monday it was putting forces on standby and reinforcing eastern Europe with more ships and fighter jets in response to a Russian troop build-u…