Top US officials have criticised the European Union for stalling trade talks, putting pressure on a transatlantic trade truce.
In July, US President Donald Trump and European Commission President Jean-Claude Juncker pledged to hold off from further tariffs and to work towards scrapping customs duties on all goods.
Both sides hailed the deal as a major breakthrough, but subsequent talks have showed that disputes persist, especially over agriculture, which Washington insists will be a key part of any agreement.
US Commerce Secretary Wilbur Ross told reporters in Brussels that Mr Trump's "patience was not unlimited" after his EU counterpart accused Washington of having a lukewarm attitude to the trade talks.
The EU considers US Trade Representative Robert Lighthizer their main interlocutor.
On Tuesday, he notified Congress that the Trump administration still intends to negotiate a free trade agreement with the EU as well as with Japan and the United Kingdom after Brexit.
EU Trade Commissioner Cecilia Malmstrom today said that the US "has not shown any big interest" in pursuing the trade deal and "the ball is in their court".
Mr Ross said: "It's as though she was at a different meeting from the one that we attended.
"Our purpose in the meeting was to address the need for speed and for getting to near-term deliverables including both tariff relief and standards," he said.
EU and US launch talks in bid to quell transatlantic trade tensions
US Ambassador to the EU Gordon Sondland accused Ms Malmstrom of "complete intransigence by her team in engaging in any meaningful way in any of issues we discussed on July 25.
"If the president sees more quotes like the one that came out today his patience will come to an end," said Mr Sondland.