The 53rd International Paris Air Show, the aerospace industry’s marquee event, is a chance to take the pulse of the $150bn-a-year commercial aircraft industry, which many analysts believe is entering a slowdown due to global pressures from trade tensions to flagging economies, highlighted by a profit warning from Lufthansa late on Sunday.

Humbled by the grounding of its 737 MAX in the wake of two fatal crashes, US giant Boeing will be looking to reassure customers and suppliers about the plane’s future and allay criticism of its handling of the months-long crisis.

French President Emmanuel Macron opened the show by unveiling a model of a proposed new fighter jet as France and Germany sign a deal for its development.

The June 17-23 show is not only about jetliner deals, but also a magnet for many of the world’s arms buyers who come to preview the latest military equipment, from anti-aircraft missiles to hotly sought cyber war-fighting capabilities.

Delegates are also watching a face-off between the United States and Iran in the Gulf where Washington blames Tehran for attacks on two tankers in a vital shipping route, raising fears of broader confrontation in the region.

In another political row with implications for arms firms attending the show, the US has threatened to cancel Turkey’s participation in the Lockheed F-35 fighter jet programme over Ankara’s purchase of the Russian S-400 missile defence system.