By Agence France-Presse
The "appetite" among European Union members is for a limited deal to open trade in industrial goods, but excluding agriculture, she said.
US President Donald Trump and European Commission President Jean-Claude Juncker announced plans for a deal in late July, in an effort to head off US threats of tariffs on auto imports.
So far, officials have been focused on preliminary work. "We haven't started negotiating yet," Malmstrom said. "I am here to continue and develop the talks."
Negotiations on a "smaller agreement focusing on industrial goods" can begin once the scope is defined, "but that would be quite limited," Malmstrom said at the German Marshall Fund.
And Juncker was "crystal clear" in his meeting with Trump that agriculture would not be included, she said.
She is due to meet with US Trade Representative Robert Lighthizer on Wednesday.
"We have been focusing this fall on regulatory cooperation, to identify fields where we can facilitate trade in certain areas," she said.
Asked about reports that Trump is considering whether to impose steep tariffs on auto imports, she said the leaders agreed that while talks were ongoing no new tariffs would be imposed.
"While we are exploring this positive agenda, there will be no additional tariffs imposed, and we are under the assumption that is still valid for the European Union."
At the meeting in July, Trump said he agreed with Juncker to "work together towards zero tariffs, zero non-tariff barriers, and zero subsidies on non-auto industrial goods."