President Donald Trump and Chinese President Xi Jinping may not be able to sign a partial trade deal until December, and two U.S. locations have been ruled out for their highly anticipated meeting, according to a person familiar with the matter.

The two sides have been trying to negotiate a limited trade deal that would entail the U.S. dropping some tariffs on Chinese imports in exchange for Beijing resuming purchases of American farm goods and other products.

The U.S.-China trade war that Trump began has been a drag on both nation’s economies, and the leaders had initially expected to take a step toward resolving it ahead of the 2020 U.S. elections at an international summit in Chile this month. The summit was canceled because of protests in the capital, Santiago.

U.S. locations for a Trump-Xi meeting that had been proposed by the White House, including Iowa and Alaska, have been ruled out, the person said. Locations in Asia and Europe are now being considered instead, the person said, asking not to be identified because the discussions aren’t public.

Reuters reported earlier that the signing might be delayed and likely wouldn’t occur in the U.S.