South Korea's presidential Blue House said Thursday Moon and Johnson spoke by phone for about half an hour ahead of the G7 gathering of world leaders from June 11 to 13, Yonhap and Newsis reported.
According to the Blue House, Johnson reportedly said he welcomes Moon's willingness to contribute to the G7, and that he expects South Korean participation in the summit to further enhance the scalability of the summit.
South Korea is attending the meeting of the world's major industrialized economies for the first time. The invitation has prompted speculation in Seoul the country could eventually be eligible for membership in an expanded G7. But last year, Tokyo, a longstanding member, expressed opposition.
Johnson and Moon have been building bilateral ties through discussions over shared concerns, including COVID-19 and climate change.
On Thursday, Moon thanked the British prime minister for his virtual attendance in the Partnering for Green Growth and the Global Goals 2030 summit in Seoul, the president's office said.
Moon said that he hopes to "actively participate" in G7 discussions for resolving global issues, including the coronavirus pandemic, economic recovery and a collective response to climate change.
Johnson said South Korea is an "important partner." The prime minister also said he welcomes South Korean investments in the digital sector and green businesses.
Modi will attend the meeting virtually due to the pandemic in India, Sky News reported. President of the European Council Charles Michel and President of the European Commission Ursula von der Leyen also are to attend, according to the report.