on the sidelines of #3
2月以降、はじめて両首脳が挨拶を交わしました。ここのon the sidelines ofはどのような意味合いで用いられているのでしょうか。Starlightさん、どうぞ。（Green, jr.）
Abe, Putin agree to continue bilateral dialogue
Prime Minister Shinzo Abe and Russian President Vladimir Putin at their meeting in Milan, Italy, on Friday agreed to continue dialogue between their countries.
The two leaders also confirmed that they will hold a bilateral meeting again when they visit Beijing next month for the annual Asia-Pacific Economic Cooperation forum summit.
The Abe-Putin meeting in Milan took place on the sidelines of the two-day summit of the Asia-Europe Meeting, or ASEM, forum through Friday.
The previous one-on-one meeting between Abe and Putin was in Sochi, Russia, in February.
http://newsonjapan.com/html/newsdesk/article/109918.php#sthash.vYSZlzxu.dpuf
