European brokered ceasefire should read Russian brokered ceasefire.
Geopolitical challenges were created by Nuland (NATO US UK) offering cookies to those Neo Nazi fascist thugs who overthrew the democratically elected President of Ukraine. If I were Putin I would not attend the Australian jamboree and let the Russian delegation take up an observer status and watch the West stew in their own juice. If the West wishes to talk with Putin they should visit Moscow, for it is Russia that controls this particular geopolitical situation in that they can refuse payment for all its goods and services in $US petrodollars.
As an aside US seeking Iran’s help in countering their ISIS creation? The mind boggles!