A Downing Street source defended Britain amid reports that an aide to Russian president Vladimir Putin had dismissed Britain as "just a small island; no one pays any attention to them".
The source told the Press Association: "As host of guests from the world's leading countries, I'm sure the Russians will want to clarify these reported remarks, particularly at a G20 where it's a very British agenda on trade and tax.
"It highlights how a small island with great people can achieve a big footprint in the world."
Mr Putin's spokesman Dmitry Peskov denied making the comment, which was attributed to him by the BBC.
The G20 summit in St Petersburg exposed stark divisions between host Vladimir Putin and US President Obama over Syria.
War emptied the suburb of Yarmouk in southern Damascus of its people. Assad's army holds it, but their prize is a ghost town.
Even in the President's heartland of Baltimore, 95% of voters are against his policy on military intervention in Syria.