The Prime Minister said that Scotland gains from Britain's membership to international networks such as the Commonwealth, NATO and the EU.
He said it send a wider message that Britain "counts for something in the world".
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Two pilots have been arrested on suspicion of being under the influence of alcohol as they prepared to fly from Scotland to the New York.
Two teenagers have been arrested on suspicion of drugs offences following the death of a 17-year-old youth who collapsed at Leeds Festival.
Theresa May will gather Cabinet ministers together on Wednesday to discuss her plans for Brexit.