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HMRC internal manual

Oils Technical Manual

Pipelines: law and regulations: Customs and Excise Duties General Reliefs Act 1979 (CEGRA)

Section Section title Summary and comments
14 Produce of the sea or continental shelf …that the UK has rights to is not regarded as an import if it is landed directly. This applies to offshore oil - usually moved by pipeline. You should check whether VAT or customs duty is due with the VAT and customs policy teams.