China warns there will be severe consequences if Canada does not immediately release Huawei Technologies' chief financial officer, calling the case "extremely nasty".
Huawei global chief financial officer Meng Wanzhou was arrested in Canada on December 1 and faces extradition to the United States.
The US alleges Meng covered up her company's links to a firm that tried to sell equipment to Iran despite sanctions.
The executive is the daughter of Huawei's founder.
If extradited to the US, Meng would face charges of conspiracy to defraud multiple financial institutions, a Canadian court heard on Friday.
Each charge has a maximum sentence of 30 years.
No decision was reached at the extradition hearing after nearly six hours of arguments and counter-arguments, and the hearing was adjourned until Monday.
China's Vice Foreign Minister Le Yucheng issued a warning demanding Meng's release to Canada's ambassador in Beijing, summoning him to lodge a "strong protest", China's Foreign Ministry said in a statement.
Le said Canada's arrest of Meng while she was changing plane in Vancouver was a serious breach of her lawful rights.
The move "ignored the law, was unreasonable" and was in its very nature "extremely nasty", he added.
"China strongly urges the Canadian side to immediately release the detained person, and earnestly protect their lawful, legitimate rights, otherwise Canada must accept full responsibility for the serious consequences caused," the statement said.
There was no immediate reaction from the office of Canadian Foreign Minister Chrystia Freeland on Saturday.
When asked about the possible Chinese backlash over Meng's arrest, Prime Minister Justin Trudeau told reporters that Canada had a very good relationship with Beijing.
Former Canadian ambassador to China David Mulroney said there will probably be "a deep freeze" with the Chinese in high-level visits and exchanges.
"The ability to talk about free trade will be put in the ice box for a while," he said.
"But we're going to have to live with that. That's the price of dealing with a country like China."
Meng's arrest was on the same day that US President Donald Trump met in Argentina with China's Xi Jinping to look for ways to resolve an escalating trade war between the world's two largest economies.
The news of her arrest has roiled stock markets and drawn condemnation from Chinese authorities, although Trump and his top economic advisers have played down its importance to trade talks after the two leaders agreed to a truce.
A Huawei spokesman said on Friday the company has "every confidence that the Canadian and US legal systems will reach the right conclusion".
The company has said it complies with all applicable export control and sanctions laws and other regulations.
