China has struck a more aggressive tone in its trade war with the US, suggesting more talks between the world’s two largest economies would be meaningless unless Washington changes course.

The tough talk on Friday capped a week that saw Beijing unveil fresh retaliatory tariffs, US officials accuse China of backtracking on promises made during months of discussions and the Trump administration level a potentially crippling blow against one of China’s biggest and most successful companies.

Asked about state media reports suggesting there would be no more trade negotiations, Chinese foreign ministry spokesman Lu Kang said China always encouraged resolving disputes with the US through dialogue and consultations.

“But because of certain things the US side has done during the previous China-US trade consultations, we believe if there is meaning for these talks, there must be a show of sincerity,” he told a daily news briefing.

The US raised Beijing’s ire this week when it announced it was putting Huawei Technologies, the world’s biggest telecoms equipment maker, on a blacklist that could make it extremely hard to do business with US companies.

China has yet to say whether or how it will retaliate, although its state media is sounding an increasingly strident note. The ruling Communist Party’s People’s Daily published on Friday a front-page commentary that evoked the patriotic spirit of the country’s past wars.

“The trade war can’t bring China down. It will only harden us to grow stronger,” it said.

Global stocks, which rebounded this week on the prospect of another round of US-China talks, suffered a fresh bout of selling and China’s yuan slid to its weakest against the US dollar in almost five months. Prices of US government debt were trading higher.

The increasingly acrimonious trade dispute has rattled investors who fear that the countries are careening dangerously down a track that will badly damage global supply lines and put the brakes on an already slowing world economy.

The South China Morning Post, citing an unidentified source, reported that a senior member of China’s Communist Party said the trade war could reduce China’s 2019 economic growth by 1 percentage point in the worst-case scenario.