Related Clues:

• New directions signs for Channel
• Gets less wide
• Becomes less wide
• In space, restricts new weapons
• Part of River Dart dividing north from south?
• Oars used by sailors going back across a stretch of river
• Poles concealing missile contracts
• Diets, with "down"
• Tapers to a point over the indicators
• The straits to which one is reduced?
• Gets smaller in width
• Loses width
• Strait formed by two rivers on the edge of Oxfordshire engaged in swan-upping
• Contracts for Polar missiles?
• Channel indicator stuck between numerous limits