An excavator works at the crash site of an Ethiopian Airlines' aircraft, some 50 km east of Addis Ababa, capital of Ethiopia, on March 10, 2019. All 157 people aboard Ethiopian Airlines flight were confirmed dead as Africa's fastest growing airline witnessed the worst-ever incident in its history. The incident on Sunday, which involved a Boeing 737-800 MAX, occurred a few minutes after the aircraft took off from Addis Ababa Bole International Airport to Nairobi, Kenya. It crashed around Bishoftu town, the airline said. (Xinhua/Wang Shoubao)

BEIJING, March 13 (Xinhua) -- More countrie have joined the ranks grounding Boeing 737 Max 8 aircraft amid mounting safety concerns after the second crash of the same model in less than five months.

After assessing information related to operations of 737 Max, "to ensure flight safety," Vietnam decided to close its air space to 737 Max since 10:00 a.m. local time (0300 GMT) of Wednesday, Vietnam's Civil Aviation Authority announced on its website.

Oman "is temporarily suspending operations of Boeing 737 MAX aircraft into and out of all Omani airports until further notice," the country's Public Authority for Civil Aviation tweeted Tuesday.

Due to the grounding, the national airline Oman Air said on its website that it will cancel a number of flights on March 12-19.

The United Arab Emirates (UAE), another key market for aircraft on the Arabian Peninsula, also banned the operation of all 737 Max 8 models "to ensure the safety of the UAE's civil aviation industry and the public," Emirates News Agency said Tuesday.

Countries that have ordered similar grounding include India, Poland, New Zealand, Fiji, Italy, Turkey, France, Germany, Britain, Malaysia, Australia, Singapore, and China, among others.

The European Union Aviation Safety Agency published Tuesday an Airworthiness Directive, suspending flight operations of both 737 MAX 8 and MAX 9 models in Europe.

Roughly two-thirds of the 737 MAX 8 aircraft in the world have been pulled from use by airlines and aviation regulators, according to a The New York Times article on Tuesday.

An Ethiopian Airlines aircraft, a Boeing 737 MAX 8, crashed shortly after taking off from the Ethiopian capital Addis Ababa on Sunday morning local time, killing all 157 people on board.

In October 2018, a Lion Air plane, also a 737 MAX 8, crashed into the sea off the Indonesian capital Jakarta, killing all 189 people on board.

Despite the two crashes, Boeing said in a statement on Tuesday that it has "full confidence in the safety of the 737 MAX," adding that "safety is Boeing's number one priority."

It on the same day ruled out any new guidance for 737 Max operators, though concerns of some customers and air carriers spread.

The aerospace company has the backing of U.S. Federal Aviation Administration, which on Tuesday said it saw "no basis" to ground Boeing 737 Max planes.

The United States, nevertheless, saw uproar domestically. In Chicago, roughly three dozen lawsuits have been filed against Boeing.