LONDON (Reuters) -Sanctions-hit Alrosa kept diamond sales in the first half of 2023 at the year-ago levels, the Russian company said on Monday as it reported financial results for the first time since Moscow's 2022 invasion of Ukraine. Efforts to reduce Russia's revenue from diamond exports and to build on Washington's existing sanctions on Alrosa, the world's largest producer, have been subject to discussions among leaders of the Group of Seven (G7) nations. Alrosa's first-half revenue totalled 188.2 billion roubles ($1.9 billion), up 0.2% from January-June 2022, an...