Boeing has announced it will release new flight control software in the wake of a second crash involving its 737 Max fleet.

New Zealand's Civil Aviation Authority (CAA) has suspended the operation of Boeing 737 Max 8 aircraft to or from New Zealand.

It follows similar moves from other aviation regulators internationally after the Ethiopian Airlines crash that killed all 157 people on board.

Boeing expressed its condolences to those who lost loved ones in the Ethiopian crash and said it had been developing the flight control software enhancement for the 737 MAX to improve safety since the October crash in which a Lion Air plane plunged into the sea killing 189 people.

"Boeing has been working closely with the Federal Aviation Administration (FAA) on development, planning and certification of the software enhancement, and it will be deployed across the 737 MAX fleet in the coming weeks," the company statement says.

There will also be updates to pilot displays, operations manuals and crew training.

The aircraft company said there were already procedures in place to safely handle the unlikely event of false data being sent to the autopilot.

CAA say on Wednesday that Fiji Airways was the only operator flying the Max 8 aircraft into New Zealand, and the airline is promising to minimise disruption by using replacement aircraft.

CAA director Graeme Harris says the next scheduled flight was not due until Thursday afternoon, giving CAA time to thoroughly review concerns about the B737 Max series aircraft after the tragic accidents involving the type in Indonesian and Ethiopia

"The decision to suspend operations by the aircraft follows recent discussions with other aviation authorities, including the US Federal Aviation Administration (FAA) which have responsibility for oversight of the design of the aircraft.

"The CAA's assessment has taken into consideration the level of uncertainty regarding the cause of the recent Ethiopian Airlines accident plus its review of the aircraft design."

Harris says the temporary suspension would remain in place while CAA analysed information as it came to hand to determine the safety risks of continued operation of the Boeing 737 Max to and from New Zealand.

Transport Minister Phil Twyford says he is confident in the aviation authority's response.

"The civil aviation community is highly networked. These decisions are made very collaboratively, and while it's always a judgement call, I think the CAA has handled it fine," Phil says.

After initially opting to continue its New Zealand flights, Fiji Airways said that, in line with the stance taken by aviation regulators, it had decided to temporarily ground its fleet of Boeing 737 MAX aircraft until more information was known about the cause of the Ethiopian accident.

The airline says it runs 17 to 21 flights a week to and from New Zealand. Of that only about 4 or 5 were operated by the Max 8s, and it would instead use its Boeing 737 NG aircraft as well its Airbus A330 fleet.

"Fiji Airways is hopeful of a smooth transition with minimal disruption to passengers. We will have the capacity to manage the change of aircraft type.

"This process has gone into immediate effect and we intend to operate schedules as planned. Any changes will be communicated to passengers," says a Fiji Airways spokesman.

Fiji Airways started flying the Max 8 aircraft from Nadi to Wellington in December last year and said continuous flight data monitoring had not identified any issues were that cause for concern.

"However, out of deference to the position taken by regulators in our region, and in response to the concerns expressed by the general public, both Fiji Airways and the Civil Aviation Authority of Fiji have agreed that the most appropriate course is to impose this temporary grounding.

"We will continue to monitor developments closely, and this decision will be reviewed in light of any new information," the airline says.

House of Travel commercial director Brent Thomas says leading up to the CAA decision agents had received a growing number of calls from New Zealanders due to fly to Fiji on the aircraft.

"It's a less than 100, but more than a handful."

Most of the Fiji bookings were for the April school holidays and later in the year.

Agents were also assisting customers all over the world who were due to fly legs on 737 Max 8s with other carriers that have now had their aircraft grounded by aviation authorities.

Brent says the Under Fair Trading Act and the Consumer Guarantees Act, the airline would have to reimburse customers if it could not provide the service they had paid for.

Other costs incurred through rebooking accommodation and transfers might be covered by travel insurance, but policies would vary.

"But they [travellers] cannot now take out insurance for it because it's a known event."

Brent says Fiji was a very popular destination which attracted 100,000 Kiwis annually, and an estimated 40 per cent of those travelled on Fiji Airways flights out of Auckland, Wellington and Christchurch.

"Given the number of aircraft and movements it's going to be thousands in a week."

Australia's Civil Aviation Safety Authority say late on Tuesday that it was banning airlines from using the planes in the country. Fiji Airways announced it would change the aircraft type operating to/from Sydney, Brisbane, Melbourne and Adelaide until further advised.

Fiji Airways currently flies two 737 Max 8s aircraft and has three on order for 2019. The airline flies the aircraft to Australia, New Zealand, Hawaii, Kiribati, Samoa, Solomon Islands, Tonga and Vanuatu.

The United States' Federal Aviation Administration (FAA) has given the Max 8 a green light to keep flying. US aviation experts have joined the investigation into the crash in Ethiopia.

The aircraft, which has been the fastest-selling airplane in Boeing's history, was recently at the centre of another investigation after the October crash involving Indonesian airline Lion Air.

Aviation authorities in Europe, including the UK, Germany, France, Ireland, Belgium, Poland, the Netherlands and Austria, all grounded the aircraft in their countries early on Wednesday morning, NZ time.

The UK was the first European nation to place restrictions on the Boeing 737 Max 8. The country's civil aviation authority said the move was a "precautionary measure" because it did not have sufficient information about the crash. Just five Max 8 planes operate in Britain, but those operated by other carriers will no longer be allowed into its airspace.

The world's biggest planemaker, which has seen billions of dollars wiped off its market value, says it understood the decisions but retained "full confidence" in the 737 Max and had safety as its priority.

Singapore temporarily suspended Max 8 flights on Tuesday, which will affect SilkAir, an arm of Singapore Airlines, as well as China Southern Airlines, Garuda Indonesia, Shandong Airlines and Thai Lion Air. The civil aviation authority of Singapore says in a statement that the suspension will be "reviewed as relevant safety information becomes available."

Australia's national carriers don't currently use the Max 8 planes. Virgin Australia had previously ordered 30 of the Boeing 737 Max 8s and 10 Boeing 737 Max 10s, but they are not yet in service - the first of the new aircraft are due to be delivered at the end of the year. Qantas also considered adding the Boeing Max to its fleet, but instead ordered 99 Airbus A320neo planes.

The Australian suspension instead affects Singapore's SilkAir - which flies into Darwin and Cairns but has already grounded its fleet - while Fiji Airways will have to substitute two 737 Maxs which fly into Adelaide, Sydney, Brisbane and Melbourne for other craft.

Malaysia and Oman also suspended flights on the aircraft in and out of their countries on Wednesday (NZ time). Aviation authorities in China, Indonesia, Ethiopia, Morocco and Mongolia had ordered airlines to ground their Boeing 737 Max 8 planes over Monday and Tuesday.

Some airlines have cited worried customers for grounding the planes, as experts chase details on why the latest flight crashed.

The Ethiopian Airlines aircraft's blackbox was found partially damaged.

Indonesian investigators are examining whether faulty readings from a sensor might have triggered the automatic nose-down command to the Lion Air plane, which the pilots fought unsuccessfully to overcome.

The Lion Air plane's flight data recorder showed problems with an airspeed indicator on at least four previous flights, although the airline initially said the problem was fixed.

Boeing has said it has no reason to pull the popular aircraft from the skies, but delayed it's the launch of its 777X airliner jetliner launch this week.

- With agencies

-Stuff.co.nz/Anuja_Nadkarni/Debrin_Foxcroft/Amanda_Cropp