More than 3,000 troops are taking part in "Operation Joint Warrior" in and around Galloway Forest in Dumfriesshire.
A group of British and French paratroopers are also carrying out a parachute drop near to the Braid Fell area.
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The Scottish independence referendum was threatening to turn into a huge boost for separatist movements in many countries in Europe.
The full Scottish referendum results from 32 counting stations across Scotland.
ITV Border Political Editor Peter MacMahon says we've just seen a emotional former SNP MSP appearing to concede that the Yes side has lost.