The diplomatic protocol of the reception of envoys of the Ming Dynasty and Tamerlane Empire were similar in procedure and usually the custom of the visiting envoys were respected by each side.

明与中亚帖木儿帝国接待使臣的礼仪在程序上有相似性，对来访使臣的习俗一般都予以尊重，这表明这一时期丝绸之路上国际交往的礼仪可能已形成惯例。

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Russia has named the alleged US intelligence chief in Moscow - a move seen as breaching diplomatic protocol.

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Downing Street says this is in keeping with diplomatic protocol for such occasions.

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In the highly choreographed, highly status-conscious world of diplomatic protocol, it would be hard to imagine a more blatant snub.

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