Foreign ministers and defense chiefs of the neighbors met in the US capital as Canada increasingly looks like collateral damage in a simmering US-China trade war, with Beijing at the same time working to ease trade tensions with Washington.

Canadian Foreign Minister Chrystia Freeland said authorities were acting "scrupulously" in the detention of Meng Wanzhou, the chief financial officer of telecom behemoth Huawei whom Washington wants extradited for allegedly violating US sanctions on Iran.

"We all agree that the most important thing we can do is uphold the rule of law, ensure that Ms. Meng's right to due process is respected and that the current judicial process in Canada remains apolitical," she told a joint news conference.

Freeland repeatedly said that Canada "is a rule-of-law country" that responded properly to an extradition request.

"In Canada, there has been to this point no political interference in this issue at all," she said.

Secretary of State Mike Pompeo said the United States was also "respecting the rule of law each step along the way" as it seeks Meng.