Related Clues:

• See 19 Across
• ''Nope!''
• "Out of the question!"
• Informal refusal
• ''Don't hold your breath!''
• On the 31st of February
• 'Unh-uh'
• ''Not a chance!''
• Informal turndown
• ''The deal is off!''
• 'No way, no how!'
• 'Never gonna happen'
• 'Not on your life!'
• 'When hell freezes over'
• Under no conditions