The invitation would be a relief for Putin, after sanctions and isolation resulting from the war against Ukraine.
If he came, it would probably be a big help, Trump says.
Prime Minister Ulf Kristersson does not share that view, but says it is too early to decide whether other major power leaders should boycott the meeting.
We will have to come back to that question. I think it has been a strength that the free world has stood united against Russia, he says at the EU summit in Cyprus.
The US is hosting the G20 summit in Florida this year, in December. Trump is also objecting to Russia's exclusion from the smaller G8 group in 2014.
President Putin was very offended by that - and rightly so, Trump says.
What do you think?