United States national security adviser Robert O’Brien said on Saturday that an initial trade agreement with China is still possible by the end of the year, but warned Washington would not turn a blind eye to what happens in Hong Kong.

The comments add to growing worries that a Chinese crackdown on anti-government protests in Hong Kong could further complicate the efforts by the United States and China to end a prolonged trade war that has roiled global markets and undercut global economic growth forecasts.

“We were hoping to have (a phase one) deal done by the end of the year. I still think that’s possible,” O’Brien told reporters at a security conference in Halifax.

“At the same time, we’re not going to turn a blind eye to what’s happening in Hong Kong or what’s happening in the South China Sea, or other areas of the world where we’re concerned about China’s activity,” he said.

He said that he hoped district elections in Hong Kong would proceed without violence. “That would be a good sign,” he said.

President Donald Trump on Friday said he had told Chinese President Xi Jinping that crushing the Hong Kong protesters would have “a tremendous negative impact” on efforts to reach an accord to end a 16-month trade war.

He has been vague about whether he would sign or veto US legislation to back protesters in Hong Kong, and boasted that he alone had prevented Beijing from crushing the demonstrations with a million soldiers.