Donald Trump’s unwillingness to back down from a trade war with China is likely to cost the U.S. one million jobs.

That’s according to Jack Ma, the billionaire founder of the e-commerce giant Alibaba who promised Trump last year that investment in the company’s presence in the U.S. would lead to up to one million extra jobs for small American businesses over the course of the next five years.

Those jobs are now lost, Ma says.

“This commitment is based on friendly China-U.S. cooperation and the rational and objective premise of bilateral trade,” Ma told the state-run Xinhua news agency on Wednesday. “The current situation has already destroyed the original premise. There is no way to deliver the promise.”

He also warned that “trade is not a weapon, it cannot be used for war, it should be a propeller for peace.”

The situation Ma is talking about is the escalating trade war between the two superpowers. On Monday Trump followed through on a threat to impose 10 percent tariffs on $200 billion worth of goods from China, with Beijing retaliating by slapping taxes of between five and 10 percent on $60 billion worth of U.S. goods.

Ma initially made the pledge to help create a million new jobs in January 2017, in a meeting with Trump just before his inauguration. Trump at the time said: “Jack and I are going to do some great things.”

While Ma’s comments today will be seen as a blow to the U.S. jobs market, some analysts had already poured cold water on the chances that Alibaba could meet its target.

On Thursday at the World Economic Forum in Tianjin Ma reiterated his prediction that the current impasse could last for decades, warning people to prepare for 20 years of China-U.S. trade frictions.