BEIJING — As Huawei’s finance chief and daughter of its founder, Meng Wanzhou has been a polished, professional face for a huge technology firm that long was opaque to the outside world.
Ms. Meng, the eldest daughter of Ren Zhengfei, the leader of the telecom equipment maker, has appeared before reporters to announce the company’s financial results. She has spoken at company events in New York; Cancún, Mexico; and beyond. She helped inaugurate facilities in Britain, a key market for the Chinese giant’s expansion into the Western world.
She also sat on the board of a Huawei partner company in Hong Kong called Skycom Tech that Canadian authorities now say did business in Iran. And through that position and her job at Huawei, Ms. Meng may have personally been involved in tricking financial institutions into making transactions that violated United States sanctions against Iran, they said.
That has thrust Ms. Meng, 46, into the center of what promises to be a complex diplomatic tussle between the United States and China. She was arrested last week in Vancouver, Canada, while changing flights, at the request of the American government, which is seeking to extradite her. The action escalated what had already been a roller-coaster year of economic conflict between the two powers, ahead of tricky negotiations to end a brutal trade war.
Huawei has said that it is not aware of any wrongdoing by Ms. Meng, and China’s Foreign Ministry has called for her immediate release.
But on Friday, in a bail hearing in British Columbia’s Supreme Court, Canadian authorities said Ms. Meng was accused of fraud. They said she had “direct involvement” with Huawei’s representations to banks, telling at least one financial executive that Huawei and Skycom were operating in Iran in strict compliance with United States sanctions when that was not the case.
Larry Kudlow, director of the White House’s National Economic Council, said on CNBC on Friday that the United States had repeatedly warned Huawei about violating American sanctions on Iran.
“We have these sanctions on Iran, it runs against our policy, why shouldn’t we enforce that?” he said.
For years, Ms. Meng’s name has appeared in connection with Huawei’s business in Iran, the subject of a yearslong United States investigation.
Reuters reported several years ago that Skycom, one of Huawei’s partners in that country, had tried to sell Hewlett-Packard equipment to an Iranian telecom carrier in 2010. The sale, which Huawei said was never completed, would have violated Washington’s ban on exporting computer products to Iran.
Huawei said at the time that its Iranian business was entirely lawful, and that it required its local partners to heed the same laws and regulations.
According to Hong Kong corporate filings, Ms. Meng was a member of Skycom’s board from February 2008 to April 2009.
In a May 2007 filing, Skycom reported that all of the company’s shares had been transferred earlier that year to a Hong Kong company called Hua Ying Management. In August 2007, Hua Ying reported to the Hong Kong authorities that its company secretary was Ms. Meng.
Ms. Meng, who started at Huawei as a secretary 25 years ago, is not its most prominent executive. But as chief financial officer, she has played a part in the company’s efforts over the past five years to become more transparent about its operations. After United States lawmakers labeled Huawei and another Chinese manufacturer, ZTE, as security threats, Huawei saw openness as a way to help dispel the swirl of suspicions surrounding it.
Some of the distrust has had to do with Ms. Meng’s powerful and secretive father.
Mr. Ren, 74, was a member of the Chinese military’s engineering corps for nearly a decade before starting Huawei in 1987. His military service has informed American officials’ concerns that Huawei has links to the Chinese government or the Communist Party — something the company has strenuously denied.
“She’s very presentable,” Duncan Clark, the chairman of the advisory firm BDA China, who once did consulting work for Huawei, said of Ms. Meng.
That is a stark contrast with her father, Mr. Clark added. “He is, for me at least, refreshingly unpolished and direct.”
For many people in China, Huawei represents how far their nation has come since it began climbing out of the economic ravages left by Chairman Mao — and how far it can continue to go.
Over the past three decades, Huawei has transformed from a small maker of telephone switches into the world’s largest supplier of telecommunications equipment, as well as the No. 2 smartphone maker, behind Samsung. The company has worked to build a consumer brand associated with quality and innovation. The name “Huawei” means “China’s Achievement.”
But after winning over cellular providers across the developing world with its cost-effective networking gear, the company faced a tougher task convincing large carriers in the wealthier nations of Europe and North America.
For many years, Mr. Ren’s reluctance to appear in public, combined with the company’s aversion to the news media, even after it had become a globe-straddling giant, fed the impression that he and Huawei had something to hide. How much of the company did he own? How did key decisions get made? Could there really be a military link?
Ms. Meng became part of an attempt to address such issues in January 2013, when she was brought before reporters in Beijing to discuss Huawei’s business outlook. The company, which is privately held, had published some financial details before. But it had never held a news conference of this kind.
“We will honor our commitment to transparency and openness,” Ms. Meng said then.
This commitment has failed to persuade the United States government that Huawei’s products are safe to use, but the company has become a supplier to many of the biggest telecom providers in Europe.
Earlier this year, Ms. Meng was made Huawei’s deputy chairwoman in addition to finance chief, leading some to wonder whether she might succeed her father at the top someday. But hers was not an heiress’s upbringing.
Ms. Meng, who also uses the names Sabrina and Cathy, was born in 1972 in the western city of Chengdu, to Mr. Ren’s first wife, Meng Jun. The family moved to Shenzhen, in China’s south, during the turbulent economic reforms of the 1980s.
Shenzhen eventually became a boomtown, a hub of China’s mighty manufacturing base and home to Huawei’s global headquarters. Back then, it was a backwater.
As Ms. Meng later recalled in a Huawei employee newspaper, the walls of the family’s house let in all the neighbors’ chatter. The roof leaked. When it rained — which it did constantly in southern China — everything got wet.
After college, Ms. Meng hoped to attend graduate school in the United States. A university gave her an offer, she recalled in a 2016 speech. But her visa was rejected because an American consular interviewer decided that her English was too poor.
Ms. Meng found a job at a bank instead. She was laid off after a year. In 1993, she joined fledgling Huawei as one of its three secretaries.
She answered the phone, printed out documents and put together product catalogs. A few years later, after completing a master’s degree in management, she returned to Huawei, this time in the finance department. And she began climbing the ladder.
As Huawei’s business spread across the world in the 2000s, Ms. Meng helped expand its accounting operations with it. Her brother, Ren Ping, works for a Huawei-owned company. Annabel Yao, a daughter of the elder Mr. Ren by his second wife, is an undergraduate at Harvard.