The latter is an issue of particularly high sensitivity to Europe after months of tension with Moscow, which supplies nearly a third of Europe`s oil and gas.
While it is the first time Russia will not be at the table since joining the club in 1997, Putin will still hold one-on-one talks with German Chancellor Angela Merkel, Britain`s David Cameron and French President Francois Hollande this week, on the sidelines of the 70th anniversary of the D-Day landings.
The decision to drop Russia from the group was taken by its other members - the United States, Germany, France, Britain, Canada, Japan and Italy - in March, after Moscow seized Crimea and annexed it, a move not recognized internationally.
Since then, the EU and the United States have imposed travel bans and asset freezes on senior Russian and Crimean officials and threatened to apply much harder-hitting economic and trade measures if Moscow is deemed for have further destabilized eastern Ukraine.
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