The six men and women who have been UK prime ministers seldom mix together except for solemn occasions such as funerals and Remembrance Sunday.
The dinner to mark a century of prime ministers living at Chequers this weekend is not going to be the cheerful joint celebration which the mansion's trustees were hoping for.
Four of the living premiers - David Cameron, Gordon Brown, Tony Blair and Sir John Major - have turned down their invitations, pleading previous engagements.
SUBSCRIBE to our YouTube channel for more videos: www.youtube.com/skynews
Follow us on Twitter: twitter.com/skynews
Like us on Facebook: www.facebook.com/skynews
Follow us on Instagram: www.instagram.com/skynews
For more content go to news.sky.com and download our apps:
Sky News videos are now available in Spanish here/Los video de Sky News están disponibles en español aquí www.youtube.com/channel/skynewsespanol