US President Donald Trump said he has not agreed to roll back tariffs on Chinese imports, dampening recent optimism for a major de-escalation in the US-China trade war.

Amid a steady stream of conflicting reports, Trump’s remarks appeared to push back against Beijing’s claims that the two sides had agreed to remove tariffs in stages as part of a partial deal announced last month. Hopes for progress in defusing trade tensions have driven global stocks higher this month, since an agreement would remove a major source of uncertainty in the world economy that is undercutting growth. But Trump again portrayed the dispute as a boon for the United States despite the tariffs paid by American companies and consumers.

“They would like to have a rollback. I haven’t agreed to anything,” Trump told reporters at the White House. “China would like to get somewhat of a rollback, not a complete rollback, because they know I won’t do it.”Beijing, however, said this week the two sides had already agreed to mutual tariff reductions.

Commerce Ministry spokesman Gao Feng announced on Thursday that negotiators “agreed to roll back the additional tariffs in stages, as progress is made towards a agreement.”

The United States and China have imposed steep tariffs on hundreds of billions of dollars in two-way trade, and another round of US duties are set to hit on December 15 on USD 160 billion in Chinese goods.