Trump will hold meetings with British Prime Minster Theresa May, President Joko Widodo of Indonesia, Prime Minister Lee Hsien Loong of Singapore, Japanese Prime Minister Shinzo Abe and President Xi Jinping of China.
To take things forward, Donald Trump will need to visit London.
President Trump said he looks forward to "a lot of very positive things happening, for Russian Federation and for the United States and for everybody concerned".
Britain can not seal a separate trade deal with the United States until it has left the European Union in 2019.
Trump met with May on Saturday on the sidelines of the G-20 summit in Hamburg, Germany.
"We are working on a trade deal - a very, very big deal, a very powerful deal, great for both countries, and I think we'll have that done very, very quickly".
She also said she was optimistic about the other trade deals the United Kingdom can get around the world, highlighting China, the US, India and Japan as potential new partners.
British Prime Minister Theresa May said Saturday that she's looking forward to welcoming U.S. President Donald Trump to London, but both sides still are working to find a "suitable date". Asked when, he replied: "We'll work that out".
Britain's Prime Minister Theresa May talks with US President Donald Trump during the G20 leaders summit in Hamburg, Germany July 8, 2017.
Ahead of their meeting, Trump hailed the "very special relationship" he had developed with May.
May was the first leader to officially visit Trump, but the prime minister faced a barrage of criticism upon her return by MPs who questioned whether Britain should develop such a close relationship with the controversial leader.
Japan's new trade deal with the European Union, signed off on Thursday, "could form the basis" of an agreement between London and Tokyo following Brexit, May told the Prime Minister.
Christopher Meyer, a former British ambassador to Washington, said Trump's statement of intent was a "very good sign for the future" and would be "useful" to May.
One of Mrs May's challenges in meeting the US President is to get him to rejoin multilateral efforts on trade and climate change.
Merkel said: "The discussions are very hard, I don't want to talk around that".