Canada will have the support of the United States until the two Canadians detained in China "are returned to their families," U.S. Secretary of State Mike Pompeo promised Thursday while on a visit to Ottawa.

Pompeo, a high-profile member of the Trump administration, met with Prime Minister Justin Trudeau and his counterpart Foreign Affairs Minister Chrystia Freeland ahead of the G7 summit in France this weekend.

Canada has been soliciting help from foreign allies in the ongoing dispute with China to secure the release of businessman Michael Spavor and Michael Kovrig, a former diplomat on leave. The two were detained in China late last year after Canadian officials arrested Chinese telecom executive Meng Wanzhou at the Vancouver airport to face possible extradition to the United States.

"Our team is focused on helping those two Canadians be released. China needs to honour the commitments it's made to the world, and it is our expectation they'll do so, and we're working on it diligently," said Pompeo during a brief photo opportunity Thursday morning.

Pompeo also made a point of insisting that the cases of Kovrig and Spavor shouldn't be compared to Meng's extradition case.

"[China] wants to talk about these two as if they are equivalent, as if they are morally similar, which they fundamentally are not," he said during a media availability on Thursday afternoon.

"These are fundamentally different matters than the Canadian decision to use their due process and the rule of law to behave in a way that's deeply consistent with the way decent nations work."

Watch: Freeland and Pompeo on China

US Secretary of State Mike Pompeo met with Foreign Affairs Minister Chrystia Freeland Thursday in Ottawa 2:48

The U.S., through a one-on-one conversation between President Donald Trump and Chinese President Xi Jinping and "other diplomatic activity," has told Beijing directly the arrest of the two Canadians was inappropriate, said Pompeo.

"We'll continue to do that until such time as they're home and returned to their families," he said.

China lashes out at Canada

Hours before their meetings got underway in Ottawa, a Chinese Foreign Ministry spokesperson called again for Meng's immediate release.

Canadian Prime Minister Justin Trudeau, right, is meeting with U.S. Secretary of State Mike Pompeo on Parliament Hill in Ottawa on Thursday. (Adrian Wyld/The Canadian Press)

"We urge the Canadian side to reflect on its mistakes, take China's stern position and concerns seriously, and immediately release Meng Wanzhou so she can return home to China safely," said Geng Shung from Beijing.

"As a Chinese saying goes: Loudness is not necessarily persuasive, and justice naturally inhabits a man's heart."

The comments out of Beijing came in the wake of a foreign policy speech Trudeau delivered on Wednesday. Addressing a gathering of the Montreal Council on Foreign Relations, Trudeau vowed that Canada would stand up to China in a climate of increased bilateral tensions.

"We do not escalate, but we also don't back down," the prime minister said.

Geng also signalled Beijing's displeasure with Canada for commenting on the ongoing protests in Hong Kong and repeated his government's call for Canada to "stop interfering in China's internal affairs."

On the weekend, Freeland and EU foreign policy chief Federica Mogherini issued a joint statement with the European Union in defence of the "fundamental right of assembly" for Hong Kong citizens.

The protests began as a response to a bill that would have allowed authorities to extradite Hong Kong citizens accused of crimes to face trial in mainland China. The bill has been suspended, but the protests have morphed into a larger pro-democracy movement.

Trudeau will have a chance to once again raise Canada's concerns with China with Trump when the two leaders hold a bilateral meeting on the sidelines of the G7 meeting.