As tensions between China and the US mount over trade and the extradition of a senior Huawei executive, Beijing has reserved its most colourful language for America’s allies.

On Tuesday, China’s ministry of foreign affairs called on Canada to “stop pulling chestnuts out of the fire for the US” after the unsealing of a 13-count indictment against the Huawei chief financial officer, Meng Wanzhou, who was arrested in Canada in December. An editorial in the state-run Global Times put it more bluntly: “You cannot live the life of a whore and expect a monument to your chastity … If Canada insists on wrong practice, it must pay for it.”

Analysts say China is trying to isolate the US by going after its allies. Two Canadians remain in detention in China over unspecified allegations of endangering national security and a third was sentenced to death for drug smuggling after a sudden retrial — cases widely believed to be retaliation for Ottawa’s arrest of Meng at the request of the US.

“China is trying to divide and conquer. It wants to put maximum pressure on individual countries and not have them band together,” said Thomas Wright, director of the Center on the United States and Europe at the Brookings Institution in Washington.

Canada is not the only US ally to get on the wrong side of Beijing. Chinese state media called Poland an “accomplice of the US”, saying Warsaw “must pay for the offence” after Polish authorities arrested a Huawei employee on suspicions of espionage.

And an Australian-Chinese writer, Yang Hengjun, was detained in China just weeks after Australia voiced concern over China’s detention of Canadian citizens. Australian officials say they do not believe Yang’s arrest is related to the Huawei case.

“One tactic the Chinese Communist party appears to be using is to attempt to drive wedges between the US and its allies, with the goal of forcing countries to make a choice between the US and China,” said Samantha Hoffman, an analyst on Chinese security.

Under President Xi Jinping, China has departed from a decades-long policy of keeping a low profile, to assert itself more on the international stage. China is wooing more countries with economic projects such as the “belt and road” initiative, a massive global investment and trade push that will involve more than 70 countries and more than a third of global GDP.

Under their president, Xi Jinping, China has begun to assert itself more on the international stage. Photograph: Lintao Zhang/Getty Images

As China’s economic presence grows worldwide, its lobbying efforts have expanded to Nato allies and other US partners previously outside the traditional range of US-China competition, according to Rorry Daniels, an Asia security expert and consultant.

“What Beijing has done is to give US allies a stake in China’s continued economic growth and to use those economic ties as leverage to reward or punish allies in accordance with China’s interests,” Daniels said.

Some say Beijing’s efforts are part of a larger goal of undermining alliances altogether, as the US under Donald Trump has cast doubt on the international system. Over the past year, president Trump has questioned the common defence principle of Nato, which maintains that an attack on one member is an attack on all.

“Beijing is taking advantage of an opportunity presented by Washington,” Daniels said. “Beijing has long seen US alliances as a constraint on its ability to use its power to advance its national interests and would like to see these relationships weakened or ended.”

In addition to carrots in the form of economic incentives, observers worry Beijing is deploying increasingly larger sticks. Both Canadians, former diplomat Michael Kovrig and entrepreneur Michael Spavor, were detained within 10 days of Meng’s arrest in Canada.

That same month, a court suddenly ordered the retrial of Canadian Robert Schellenberg, previously sentenced to 15 years of prison for drug smuggling, in a case that took more than three years to settle.

“The Chinese government is making it very difficult for democratic governments to respond. Liberal democracies certainly cannot respond reciprocally to the PRC’s tactics without undermining their own political systems. Governments are also being forced into an ethical dilemma,” Hoffman said.

Such efforts could prove counterproductive, with more countries opting to take a harder line against China and blocking Huawei products and services. Germany is considering banning Huawei 5G equipment. New Zealand and Australia have already barred the use of its equipment, while BT in the UK said it had removed Huawei kit.

Others point out that China’s efforts are no different from the lobbying and diplomatic campaigns of most countries. “At the very least, they want more people to hear China’s views,” said Shi Yinhong, a professor at Renmin University and expert on US-China relations.

“What China is doing is natural, it’s not about exerting pressure. This hasn’t worked in the short term, but in the long term it will — along as China uses appropriate methods and language.”