It is not yet clear whether the Russian leader, who has faced unanimous condemnation by Western leaders for the invasion of Ukraine, will attend the meeting in Indonesia later this month.
Mr Sunak will travel to the G20 in Bali in one of his first major global outings as prime minister after briefly attending the Cop27 climate summit in Egypt on Monday.
The Prime Minister is of the view that it would be right that collectively with our allies we confront any Russian official
Prime Minister's spokesman
In Bali Mr Sunak is expected to meet fellow world leaders including US President Joe Biden.
On Tuesday Downing Street suggested that Mr Sunak would hope to use the meeting to “confront” the Russian leadership with other Western allies as the war in Ukraine continues.
The Prime Minister’s official spokesman said: “The Prime Minister is of the view that it would be right that collectively with our allies we confront any Russian official … who attends the G20 about their ongoing illegal war and use the same messages we have been using in one voice for so many months now.”
Pressed on whether Mr Sunak would sit down with Mr Putin at the summit in Bali, if the Russian leader attends, the spokesman declined to fully answer.
He told reporters that Mr Sunak “is of the view that he will speak with allies, whether it’s G7 or other allies, to further confront this illegal Russian aggression”.