Related Clues:

• Spill the beans about Blair's leadership and his party
• Chatter in workplace after introduction of bonuses
• Throw discretion out the window, in a way
• Not be a good confidant
• Flap one's gums, that's slang for 'talk incessantly'
• Spill everything
• Prove untrustworthy, in a way
• Not keep a secret
• Spill, as a secret
• Spill something in key test area
• Spill secrets of British research facility
• Be a tell-all
• Spoil the surprise
• Vestment returned by bishop let out
• Be a tattletale