What will IMF do if Greece fails to pay?

Greece is due to payback International Monetary Fund (IMF) € 1.5 billion worth of bailed out money by end of this month. Greece has already decided to bundle all the payments due this month to pay at the end, which is permitted by IMF provisions, however a payment miss by June 30^th, would be great embarrassment for  IMF.

On June 5^th, Greece decided to miss IMF payment and bundle it together to pay at the end of the month. This was great embarrassment for IMF chief Christine Lagarde, who declared that Greece will make the payment and was caught unaware completely.

So if Greece fails to pay -

• This failure to pay won't be considered as default by rating agencies since it's an official debt. It won't be default even by IMF as it like to call it arrears.
  
  
• Within a month of default, IMF chief will inform the board of IMF of such.
  
  
• After two months of default, IMF will post brief factual statement and mention the arrears in its website.
  
  
• If Greece fails to payback within two years of deadline, IMF has the power to revoke Greece's membership in IMF.

This means no end of the world immediately if Greece doesn't payback, however it would be great embarrassment for the fund who is likely to face harsh criticism from developing countries over preferential over exposure.