OTTAWA -- Canada鈥檚 health minister said Tuesday that delays in evacuating Canadians from Wuhan, China are due to an unexpected number of requests for assistance -- and the government had initially hoped to use seats on flights from allied countries.

鈥淭he delay in terms of the first plane was really not having a sense of how many Canadians needed that support,鈥 Patty Hajdu told reporters. 鈥淭hat led us to believe we might be able to extricate Canadians using our allied partners who had additional space on planes they were using.鈥

鈥淲e weren鈥檛 actually thinking that we had the demand that we did. Once it became clear within the next couple of days of speaking about the need to register with Global Affairs Canada it became clear we were going to need our own plane.鈥

The United States, Germany, France and Sweden are among the countries that have been able to evacuate their citizens already.

Rob Oliphant, the parliamentary secretary to the foreign affairs minister, told CTV鈥檚 Power Play that before the outbreak, roughly 30 Canadians registered abroad in Hubei province.

鈥淣ine days ago, we had two people requesting evacuation鈥nd you don鈥檛 book a plane for two people,鈥 he said. 鈥淭hen it came to 20 (and) then it came to 50, now we鈥檙e just over 300, but that鈥檚 in the last several days.鈥

Hajdu said that while 308 Canadians have asked to be repatriated from China, just 280 of them have Canadian passports. The letter confirms that only those with a valid Canadian passport containing a valid Chinese visa will be allowed to board the plane.

There are only 250 seats on the plane, Hajdu said Tuesday.

鈥淭he numbers fluctuate day to day,鈥 she added. 鈥淭hese are the most recent numbers I know as of yesterday. Again people sometimes change their minds as well. What we鈥檝e learned from our international partners who have already repatriated their citizens is there are a number of no shows as well.鈥

麻豆影视 has obtained a letter confirming an "assisted departure flight" is expected to evacuate some Canadians from Wuhan, China on Feb. 6.

The letter cautions that not everyone who is eligible for a seat will be able to board the plane due to "demand" and "restrictions associated with this flight." It also says travellers exhibiting symptoms of the new coronavirus will not be allowed to board the plane.

, Foreign Affairs Minister François-Philippe Champagne said the plane is currently on its way to Hanoi, Vietnam, where it will be "prepositioned" for its trip to China "when final approvals are granted."

The passengers who arrive in Canada on that flight will need to remain at Canadian Forces Base Trenton for 14 days, where "regular health assessments will be conducted." Family and friends will not be permitted to visit at that time.

"We are working to get Canadians back as quickly as we can," Prime Minister Justin Trudeau told reporters Tuesday morning.

"We're following all the proper steps to make sure that everyone's safe."

Speaking to reporters on Tuesday, Champagne said that it's possible some families could end up partially separated in cases where one parent is not a Canadian citizen.

"[China's] position, for the health emergency they're dealing with, as made clear to every government in the world 鈥 it's foreign nationals who travel on foreign passenger planes," Champagne said.

That means that while minors will not be allowed to travel unaccompanied, in cases where only one parent has citizenship, the other parent will be left behind.

In cases where a child has Canadian citizenship and their only primary caregiver does not, that caregiver will be allowed to travel with the child.

Michael Schellenberg, a Canadian trapped near Wuhan, was told on Tuesday that he, his Chinese wife and their young son are among the passengers heading to CFB Trenton later this week.

Schellenberg鈥檚 wife will be on the flight because of her child's Canadian citizenship

鈥淚 wouldn't leave my wife here,鈥 Schellenberg said. 鈥(My son) needs to breastfeed, so he's too young so that's why she was given an exception.鈥

Prime Minister Justin Trudeau confirmed that there isn't space on the plane for everyone who has requested evacuation.

"Right now there is a larger number of Canadians asking for evacuation than there is space on the plane, that's why we have already got an option on the second plane."

The PM said they have not yet decided whether the second evacuation plane will be necessary, given that not everyone who is hoping to be evacuated is always able to get to the airport. Trudeau said this is a decision the government will make based on how full the first plane is.

Trudeau added that China is being "fully co-operative" in this effort.

"There's just a lot of processes to make sure that they can get through the local quarantines on the way to the airport, that all the proper paperwork is filled out, that identities are verified and triple verified," he said.

The coronavirus has killed 425 people in China, as well as two others in Hong Kong and in the Philippines. Over 20,000 people have contracted the illness in at least 180 countries, including four confirmed cases in Canada.

All of the Canadian cases "are healthy and cleared," Hajdu told reporters on Tuesday.

The outbreak was first flagged on New Year's Eve, when a cluster of cases believed to be pneumonia were discovered in Wuhan, the capital city of China's Hubei province.

Shortly afterwards, officials realized the patients did not have pneumonia, but instead were ill with a new virus that had never before been found in humans: the 2019 novel coronavirus, or 2019-nCoV.

Health Canada describes coronaviruses as a "large family of viruses that cause illnesses ranging from the common cold to more severe diseases."

With files from CTVNews.ca Writer Ben Cousins