Under an agreement between Kabul and Washington, the U.S. military can bring equipment in and out of Afghanistan without being subject to taxes or customs duties.

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"For example products originating in Turkey, Mediterranean countries like Egypt, Jordan, Morocco, or some countries in South and Central America, may benefit from an exemption of customs duties or reduced duties, " he says.

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The OTS's remit covers UK taxes and duties administered by HM Revenue and Customs, but it will not deal with tax credits or taxes administered by other bodies nor will it have any influence on setting tax rates.

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