Two shipments of protective masks, one scheduled to arrive in Germany, the other in Canada, were diverted to the United States this week under dubious circumstances after the orders had already departed for their destinations.

German newspaper Der Tagesspiegel reported 400,000 respiratory masks intended for German police officers were redirected to the US, which is dealing the world's largest outbreak of the novel coronavirus.

The delivery from mask manufacturer 3M was shipped from China and reloaded in Bangkok before it was to be transported to Germany by air freight. However, in Bangkok, the shipment was suddenly "redirected" to the US, Berlin police confirmed.

Meanwhile, a newspaper based in the Canadian province of Quebec, Journal de Montreal, reported an order of 10,000 masks bound for the province went missing, with the delivery never arriving at its intended destination.

The US government is now recommending Americans wear cloth face coverings on a voluntary basis to stem the spread of the virus, President Donald Trump said on Friday, adding that he himself would not use one.

"What has changed in our recommendation? Well, it's important to know that we now know from recent studies that a significant portion of individuals with coronavirus lack symptoms," Surgeon General Jerome Adams said, noting that new evidence points to viral transmission via speaking, in addition to coughing and sneezing. "Even those who eventually become pre-symptomatic, meaning they will develop symptoms in the future, can transmit the virus to others before they show symptoms," he added.

Mr Trump said that the US Centres For Disease Control and Prevention are not recommending the use of medical-grade masks for most people. The President added Americans can make cloth masks at home.

'Humanitarian implications'

3M Co said on Friday it would make more face masks for the United States to fight the coronavirus pandemic, but warned of "humanitarian implications" of limiting supply to other countries as President Donald Trump directed.

The 3M headquarters in Minnesota. AFP

Mr Trump has asked 3M to ramp up imports of the masks to the US from its other global manufacturing facilities, while demanding a pause in the exports of domestically-produced respirators to Canada and some Latin American countries.

"There are, however, significant humanitarian implications of ceasing respirator supplies to healthcare workers in Canada and Latin America, where we are a critical supplier of respirators," the company said in a statement.

"I'm not at all happy with 3M," Mr Trump said when asked about the pushback his order had received from Canada and the company. "I heard what he had to say today. I don't know the gentleman, but we're not happy with 3M."

But Mr Trump took aim at states as well, saying they should have been better prepared to respond to the pandemic with their own stockpiles of medical supplies, and should not have expected the federal stockpile to meet their needs.

"Many of the states were totally unprepared for this, so we had to go into the federal stockpile," Trump said. "We're not an ordering clerk. They have to have for themselves."

"We have been spending a tremendous amount of time, effort and billions and billions of dollars on making sure that they have what they have."

Berlin's Interior Minister Andreas Geisel, who confirmed the shipment was "confiscated" in Bangkok, said: “We consider this an act of modern piracy. This is not how you deal with transatlantic partners."

"I urge the [German] federal government to urge the United States to comply with international rules."

Germany has the fourth-highest case count globally, with 85,063 cases of Covid-19 and 1,122 deaths.

Canada efforts

In Canada, a Quebec company imported the masks for use in the province, but they ended up in Ohio without explanation.

“We are doing everything we can to make sure that the orders we place go to our hospitals here in Quebec,” said Quebec Premier Francois Legault on Thursday. He did not specify from which company the order was placed.

Earlier in the week Mr Legault said that the province could run out of key medical supplies within days. He said replenishing protective medical equipment, such as N95 masks, was a "key priority".

Quebec has the highest number of coronavirus cases in Canada with 5,518 people infected with Covid-19 and 36 deaths.

Health Minister Danielle McCann noted that the supply of face masks in Quebec was so low that healthcare workers were being asked to disinfect and reuse their masks.

When Deputy Prime Minister Chrystia Freeland was asked about reports that the US is outbidding other countries in order to redirect supply of medical equipment, she said the Canadian government was working on issue but maintained that Canada has “good collaboration” with the US.

French politicians have also accused Washington of buying up shipments intended for France.

A senior US official on Thursday rejected the French allegations as “completely false”.

The leader of the Ile-de-France region, which includes Paris, accused unidentified Americans of swooping in with cash to secure shipments already promised to French buyers.

“We lost an order to the Americans who outbid us on a shipment that we had lined up,” said Valerie Pecresse, the chief of France’s most populous region.

Ms Pecresse explained that France pays on delivery for such supplies.

France is currently grappling with 59,29 cases of Covid-19 and 5,398 deaths.