Possible Clues:

• 'It's really difficult to underestimate you,' for one
• Roast remark
• Disrespectful comment concealed in Berlin’s ultimatum
• Slight stain sultanate has covered up
• Complains, ultimately taking offence
• Slight gains ultimately reduced all round
• Stalin's ultimatum contains abuse
• Show contempt to
• Slight, say
• Slap cause, maybe