MOSCOW, July 2 (Reuters) - Russia's exports of liquefied natural gas in the first half of the year declined by 4.4% from a year earlier to 15.2 million metric tons, LSEG preliminary data showed on Wednesday, amid international sanctions over Ukraine. In particular, the United States has imposed sanctions on companies and vessels linked to Russia's new Arctic LNG 2 plant because of the conflict in Ukraine, effectively freezing the project because of the difficulty for Moscow in finding buyers.