U.S. special climate envoy John Kerry’s trip to Beijing failed to yield an agreement with China on further actions to slash carbon pollution, he said Wednesday — acknowledging that “it’s going to take a little bit more work to break new ground” in talks between the world’s two biggest greenhouse gas polluters.

But Kerry said the two nations vowed to continue meeting on climate change — a modest step in the Biden administration’s efforts to restore relations with Xi Jinping’s government.

The announcement followed three days of talks aimed at formally restarting the U.S.-Chinese climate dialogue.

The trip was never expected to yield major breakthroughs. It remains unclear if growing tensions between the U.S. and China will prove a lasting obstacle to efforts to accelerate the world’s transition away from planet-heating fossil fuels.