Finance ministers from the world's biggest economies on Saturday (Shenzhen: 002291.SZ - news) dropped an anti-protectionist pledge and a vow on action against climate change, after Washington refused to sign up to the commitment.
After a two-day meeting, ministers from G20 developed and developing nations said they were "working to strengthen the contribution of trade to our economies" but failed to spell out a pledge to reject protectionism in a closing statement.
The conspicuous omission came amid a push by US President Donald Trump to pursue an "America First" policy that includes penalising companies that manufacture abroad by heavily taxing their products.
Since taking office, he has withdrawn the US from a trans-Pacific free trade pact and attacked export giants China and Germany over their massive trade surplus.
His stance has sparked alarm among Washington's trading partners, and led Beijing to issue a stern warning against sparking a trade war.
References to action against climate change under the Paris accord were also scrapped from the G20 statement unlike at a previous summit last year.
Sources said the US delegation could not commit as they had not been given instruction from Washington to do so at the meeting in the western German spa town of Baden-Baden.
The exclusion of climate marked a new setback for environmental action, activists say, after Trump proposed to take the axe to environmental financing.
Under his first national budget proposal, he suggested cutting financial resources for the Environmental Protection Agency (EPA) by a third, as well as eliminate contributions linked to the UN climate change programmes.
The failure by ministers to agree on trade and climate action was met with dismay by France, whose Finance Minister Michel Sapin said: "I regret that our discussions today were unable to reach a satisfying conclusion."
Where the US has threatened foreign manufacturers with steep import taxes, France "rejects all unilateral protectionist measures", Sapin added.