US President Donald Trump flew to Buenos Aires today for what looks set to be a fractious weekend of G20 summitry, cancelling planned talks with Russian leader Vladimir Putin and boasting that his trade war with China was paying off.
Rumblings of resistance to Trump's assault on the international order were apparent as French President Emmanuel Macron said he would convene his fellow European leaders in Buenos Aires to forge a united front on "all the challenges" faced at the G20.
Trump called off Saturday's bilateral with President Vladimir Putin at the G20 minutes after saying it would "probably" still happen despite Russia's seizure of three Ukrainian ships, as "it's a very good time to have the meeting."
"Based on the fact that the ships and sailors have not been returned to Ukraine from Russia, I have decided it would be best for all parties concerned to cancel my previously scheduled meeting in Argentina with President Vladimir Putin," he tweeted.
In Moscow, Kremlin spokesman Dmitry Peskov had said prior to Trump's Twitter announcement that even if it may be "impossible" to agree on all issues, "we need to talk" for the sake of global stability.
Reacting afterwards, Peskov said Russia had not been informed formally by the White House.
"If that is the case, the president [Putin] will have a few extra hours in his programme for useful meetings on the sidelines of the summit."
While the Putin meeting now appears off, Trump is still slated to sit down with President Xi Jinping on the G20 margins to press for wholesale reform of the world's second-biggest economy in favour of access for US companies.
After heaping huge tariffs on Chinese goods, and threatening more to come in January, Trump said a ceasefire to the trade war was "very close" – but cast doubt on whether he even wanted one.
Trump's tough talking set the stage for a contentious gathering in Argentina with the tensions over Ukraine and trade deepening fissures carved open by the US president on climate change – an issue that nearly torpedoed last year's G20.
It is likely to be to the fore of the meeting of European leaders called by Macron, along with demands to resist the trade protectionism now stalking the world economy 10 years after the first G20 summit was held in the throes of financial crisis.
G20 sources said climate change was emerging as the biggest stumbling block to agreement on a communiqué in Buenos Aires.
Trump now has an ally on that issue in Brazil's incoming, far-right president Jair Bolsonaro, their scepticism defying scientists' increasingly urgent warnings that the planetary threat is real and needs policy redress now.
G20 countries account for four-fifths of the world's economic output but the group's consensus on the biggest challenges is under assault as other members such as Italy and Mexico also fall under the sway of populist governments.
En route to Argentina, Xi vowed on Wednesday that China would "make a lot of efforts to speed up market access, improve the investment environment and increase protection of intellectual property."
But foreign firms in China complain that such promises are all too routine, and analysts doubt that Trump and Xi's talks over a working dinner will serve up much beyond a commitment to negotiate further.
The G20 summit is already confronted with dire warnings, by the International Monetary Fund among others, of the potential harm faced by the world economy from Trump's tariffs on Chinese goods and his stated threats of action to come against European and Japanese cars.