It’s been two and a half months since President Trump first proposed a new set of tariffs on consumer goods imported from China — and today, those threats were unexpectedly renewed. On Twitter, Trump complained that the Chinese government had not lived up to its trade promise, and threatened to retaliate in advance of upcoming talks with an additional 10 percent tariff on September 1st.

“We thought we had a deal with China three months ago, but sadly, China decided to renegotiate the deal prior to signing,” Trump tweeted. “More recently, China agreed to buy agriculture product[s] from the US in large quantities, but did not do so.”

“Trade talks are continuing,” he continued, “and during the talks the US will start, on September 1st, putting a small additional tariff of 10 percent on the remaining 300 billion dollars of goods and products coming from China into our country.”

In May, Trump proposed a 25 percent tariff on those same goods, so in some ways the latest threat represents a deescalation from earlier threats. However, any level of tariff would be disastrous for consumer tech companies, which are broadly dependent on both Chinese manufacturing and American customers. The previously proposed 25 percent tariffs were estimated to add $70 to the cost of every cell phone entering the country from China, with iPhone manufacturing particularly exposed to the new costs. Apple has also asked for an exemption for Mac Pro parts, an exemption the President has pledged to deny.

Many of those costs are expected to be passed directly along to consumers. Sony has warned that it will be forced to raise the price of PlayStations if new tariffs are implemented.

Trump had threatened to implement those tariffs earlier in July. “We have a long way to go with China,” he said. “We have another $325 billion we can implement, if we want.”

Still, it’s unclear how the tariffs will be implemented, and which exemptions, if any, will be granted. The US Trade Representative did not immediately respond to a request for comment on the president’s statement.