China lashed out at British Prime Minister Boris Johnson on Wednesday, claiming his decision to purge Chinese telecom company Huawei from the country’s 5G network would hurt the U.K. economy. One Chinese official said the U.K. is becoming a “vassal state” of the United States, due to the pressure from the Trump administration on Downing Street to ban Huawei.

“Now I would even say this is not only disappointing - this is disheartening,” Chinese Ambassador to the U.K. Liu Xiaoming told the Centre for European Reform in London. “The way you are treating Huawei is being followed very closely by other Chinese businesses, and it will be very difficult for other businesses to have the confidence to have more investment.”

The U.K. and China have a valuable economic relationship, with the U.K. heavily reliant on Chinese imports. In 2018, Chinese goods made up 9% of the U.K.’s imports, an equivalent of $54 billion.

In separate remarks, a spokeswoman for the Chinese Foreign Ministry also issued a harsh statement against the U.K.

“Does the U.K. want to maintain its independent status or be reduced to being a vassal of the United States, be the U.S.’s cats paw?” Chinese foreign ministry spokeswoman Hua Chunying said. “The safety of Chinese investment in the U.K. is being greatly threatened.”

The Trump administration had pressured Johnson to ban Huawei, due to concerns that the company’s telecom equipment would provide a “backdoor” for Beijing to steal confidential information. In January, Johnson had originally granted Huawei permission to develop Britain’s 5G network, prompting indignation from Trump.

In a February phone call, Trump reportedly vented “apoplectic” fury at Johnson over the move. Huawei executives had applauded Johnson’s original decision.

On Tuesday, President Trump praised the U.K.’s reversal on the issue in a White House Rose Garden address.

"We convinced many countries, many countries — I did this myself for the most part — not to use Huawei, because we think it's an unsafe security risk, it's a big security risk," Trump said.