Two of the world’s largest aero-engine makers have unveiled plans for a new generation of jet engines that promise to cut fuel consumption by 20 per cent as early as the middle of the next decade.

General Electric and Safran said they would extend their engine joint venture, CFM International, by another 10 years to 2050 as part of the commitment.

CFM is the world’s largest jet engine maker in terms of the number of units sold. Its Leap engines power both the Boeing 737 Max and Airbus A320neo planes.

The project is the latest sign of the environmental pressure on the aviation industry to prove it can decarbonise.

A big part of this challenge will fall to the engine makers, notably CFM, Britain’s Rolls-Royce and Pratt & Whitney, part of Raytheon, all of whom are developing or exploring different technologies to decrease fuel burn and emissions. The next generation of engines will need to provide a significant step-change.

“It reflects the challenge facing the aerospace and airline industries to avoid looking like the villain of the piece in the next two decades,” said Sandy Morris, analyst at Jefferies.

“Reducing aircraft emissions is an intractable problem looking out perhaps 10 to 15 years,” he added.

“We have to act now to accelerate our efforts to reduce our impact on the environment,” said Olivier Andries, Safran chief executive. The French company had previously said it was working on a successor to the Leap engine.

CFM’s demonstration programme will focus on so-called open fan architecture, an engine design with visible fan blades. It will pursue hybrid electric technologies and be compatible with both sustainable aviation fuels and hydrogen.

The aim, the two companies said, would be to lower fuel consumption and carbon dioxide emissions by 20 per cent compared with today’s engines.

“Current technology engines, such as CFM’s Leap, used on narrow-body aircraft, are now in an extended sunset phase,” said Sash Tusa of Agency Partners.

The launch of the demonstrator programme could heighten the stakes in the competition between engine makers to power the next Boeing plane.

The US group has been considering whether to launch a new aircraft to take on Airbus’s successful A320 family of jets, which have allowed it to dominate the market for narrow-bodies.

Rolls-Royce recently confirmed it was in talks with Boeing about powering a new aircraft. The UK aero-engine group is relying on its UltraFan programme of engine technologies to help it break into the market for narrow-body aircraft.

John Slattery, chief executive of GE Aviation, on Monday stressed the initiative was still in its demonstration phase, but said CFM would nevertheless be ready to compete for whatever new plane Boeing might launch.

CFM, he added, would be “ready if Boeing offers a platform”.