Xu said criticism of Huawei this week from Mike Pompeo, the US secretary of state, and calls for allies including the UK to block its technology was unwarranted and an "indication that the US government is... using a national machine against a small company - as small as a sesame seed".
He said speculation that Donald Trump might use an executive order to ban its gear from the rollout of state-of-the-art 5G telecom networks in the US would not affect Huawei.
"No matter the outcome it will not have a major impact because we have virtually no business presence there [in the US] and no expectation of a major business presence there."
He also played down further bans on Huawei technology unveiled by Australia and New Zealand, two other members of the so-called Five Eye group of intelligence-sharing nations.
"We certainly don't expect our 5G equipment to be chosen by all countries," he said.
"China Mobile didn't pick Huawei for [the city of] Guangzhou. And the market size of Australia is smaller than Guangzhou... and New Zealand is even smaller.... So, I think it's OK that we are not present in certain countries."
Xu is one of three executives who take turns serving as Huawei's chairman every six months.
"We will focus on providing good service to those companies which choose Huawei."
Xu accused the US of deliberately targeting Huawei in order to advance its interests in a trade war.
"So we have been wondering if the recent fixation on Huawei is about cybersecurity or other motivations? Some people argue that they try to find leverage for US-China trade negotiations."
He continued: "Some other people argue that because if Huawei equipment is used in those countries, US agencies would find it... harder to intercept their mobile communications."
Xu also sought to explain why in a letter to MPs Huawei said it may take up to five years and cost US$2b to make upgrades to software recommended by UK security officials last year.
He said that in order to satisfy the concerns of UK security officials, Huawei plans to completely rewrite its source code - the most basic components of its software system - a major step whose scale should not be underestimated.