The aviation industry and grieving families of victims of the March 10 crash anxiously await details from the Ethiopia-led investigation.

Boeing, which has come under scrutiny since the second crash in five months of its 737 MAX 8 model, is briefing airlines on software and training updates on the 737 MAX.

The MAX software is the focus of investigations into the two crashes - in Ethiopia this month and in Indonesia last year - in which 346 lives were lost.

A spokesman for Ethiopia's Transport Ministry, which is leading the investigation in Addis Ababa, told Reuters that the report will very likely be released this week.

The statement came a day after Ethiopian Airlines chief executive Tewolde Gebremariam said he expected the preliminary report to be released this week or next week.

Tewolde told Reuters the company may or may not attend Boeing's briefing in the United States this week.

Boeing's software fix for the grounded 737 MAX will prevent repeated operation of an anti-stall system at the centre of safety concerns.

The updated software will deactivate the anti-stall system altogether if two sensors disagree widely, two people familiar with pilot briefings told Reuters on Monday.

Upgrading an individual 737 MAX with Boeing's new software only takes about an hour per plane, though the overall process could stretch on far longer as it is rolled out across the global fleet due to stringent testing and documentation requirements by engineers and regulators, according to a senior FAA official with knowledge of the process.

Ethiopian and French investigators have pointed to "clear similarities" between the two crashes, putting pressure on Boeing and US regulators to come up with an adequate fix.

Australian Associated Press