*act on its own = 独自の行動をとる、

The OECD, a club of mostly rich countries, was meant to tackle digital non-taxation initiative called BEPS (Base Erosion and Profit Shifting). Progress, however, has been glacially slow. Fed up with waiting, Europe vowed to act on its own.

Digital taxation - A tech-taxing tangle The Economist Dec. 8th 2018 ハイテク企業に対する課税政策

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