MOSCOW, Dec 13 (Reuters) - Gazprom Neft (SIBN.MM), the oil arm of Russian gas giant Gazprom (GAZP.MM), said on Monday the government has cleared 30 billion roubles ($409 million) in loans from Sberbank (SBER.MM) and Gazprombank (GZPRI.MM) for a green project in oil refining. Gazprom Neft said both banks will provide 15 billion roubles each for the ecological modernisation of its Omsk refinery in western Siberia as part of a state-sponsored green programme. The company embarked on the refinery modernisation in 2008 and has managed to cut its environmental impact by 40%. It will be further reduced by 25% by 2025, Gazprom Neft said. ($1 = 73.4360 roubles)