That's been a kind of understanding, a tacit agreement between these countries since the late 1940s.

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But there seemed to be a tacit agreement that something had to be done.

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"There is apparently a tacit agreement between both leaders, if not coordination, to engage in very intense PDA, " or public displays of affection.

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The United States saw that public pressure as having broken the tacit agreement among all the allies not to declare support ahead of Tuesday's summit for any of the applicants.

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