Diplomatic tensions between the US and China has escalated sharply with the Trump administration’s closure of the Chinese consulate in Houston to protect “American intellectual property and private information”. A Republican senator claimed that the Texas consulate, which covered several southern states, was an “espionage hub”. China described the closure as “unprecedented” and an “outrageous” escalation, and threatened retaliation. “China strongly condemns such an outrageous and unjustified move, which will sabotage China-US relations,” the Chinese foreign ministry spokesman Wang Wenbin said at a regular news briefing on Wednesday. “We urge the US to immediately withdraw its erroneous decision, otherwise China will make legitimate and necessary reactions.” Fire services were called to the Houston consulate overnight after smoke was seen rising from the compound. US officials said staff, who were given 72 hours to leave the country, were burning documents in its grounds. It was unclear whether the closure of the consulate was triggered by a new development. During a visit to Denmark on Wednesday, the secretary of state, Mike Pompeo, suggested the move reflected a US decision to be less tolerant of Chinese behaviour. “President Trump has said ‘enough’. We’re not going to allow this to continue to happen,” Pompeo said. “We are setting out clear expectations for how the Chinese Communist party is going to behave, and when they don’t, we’re going to take actions that protect the American people, protect our security, our national security, and also protect our economy and jobs.” The state department spokeswoman Morgan Ortagus said: “The United States will not tolerate the PRC’s [People’s Republic of China’s] violations of our sovereignty and intimidation of our people, just as we have not tolerated the PRC’s unfair trade practices, theft of American jobs and other egregious behaviour.” Marco Rubio, the acting chairman of the Senate intelligence committee, said: “It’s kind of the central node of a massive spy operation: commercial espionage, defence espionage, also influence agents to try to influence Congress. They use businessmen as fronts in many cases to try to influence members of Congress and other political leaders at the state and local level. And so it’s long overdue that it’d be closed.” The consulate closure came a day after the US accused two Chinese nationals of trying to steal Covid-19 vaccine research, claims that China described as “slander” on Wednesday. This month the FBI director, Christopher Wray, said China was the “greatest long-term threat to our nation’s information and intellectual property and to our economic vitality”. The Chinese foreign ministry accused US authorities of targeting its diplomats in the US, including opening their pouches without permission “multiple times” and confiscating items intended for official use. The ministry said its embassy in the US had received bomb and death threats, the result of the US “fanning hatred against China”. Beijing accused US diplomats in China of “infiltration and interference activities”. “If we compare the two, it is only too evident which is engaged in interference, infiltration and confrontation,” it said. Ties between the two countries have deteriorated further in recent weeks as the US has taken a harder position against China and lobbied its allies to do the same. The closure of the consulate follows a tightening of restrictions for Chinese nationals working in state media in the US, which Beijing claims as the reason for it expelling more than a dozen western journalists over the last few months. On Wednesday Chinese state media suggested the possibility of closing US consulates, posting a poll on Twitter asking users to choose between missions in Hong Kong, Chengdu, Guangzhou and others. China has blamed international criticism of its passage of a harsh and broadly applied national security law in Hong Kong on the US, making the closure of the Hong Kong consulate a possible but escalatory measure. Nick Marro, a China analyst at the Economist Intelligence Unit, said: “In recent weeks we’ve seen some appetite on the Chinese side in trying to de-escalate tensions. Whether that agenda survives these recent developments will be a critical thing to watch.”