Here's the G20 Leader's declaration, which was adopted on 1 December 2018, in Buenos Aires, Argentina.
G20 Leaders’ declaration Building consensus for fair and sustainable development
At the closing session, Japan's Prime Minister made a short speech on the expected agenda for G20 Osaka Summit, which will take place in 28-29 June 2019.
https://japan.kantei.go.jp/98_abe/actions/201812/_00001.html
The Ministry of Finance, Japan, also released the statement by the Finance Minister on G20 FMCBG Meeting under the Japanese Presidency.
https://www.mof.go.jp/english/international_policy/convention/g20/20181202.htm
The Ministry of Foreign Affairs, Japan, provides related information on G20 Summit, including Leaders' Declaration, its summary and Japanese translation.
The Government of Japan opened the official website for G20 Osaka Summit.
