MILAN (Reuters) -Italian energy group Eni, which buys Russian gas under long-term take-or-pay contracts, is closely monitoring international developments in the Ukraine crisis. “Eni will fully honour every decision taken by the European and Italian institutions,” a spokesman said, when asked what the company would do with the contracts if sanctions on Russia’s energy sector tightened. Eni, whose biggest shareholder is the Italian Treasury, bought 22.5 billion cubic metres (bcm) of Russian gas in 2020 out of a total of around 62 bcm. Last week it said it would sell its stake in the Blue Stream …