Rostec State Corporation, the Russian industrial conglomerate co-developing a long-haul widebody aircraft with China, has said the two countries will develop their own engines for the project, with the apparent longer-term aim of breaking the duopoly enjoyed by General Electric and Rolls-Royce.

Victor Kladov, director of Rostec's international cooperation and regional policy, said the development and manufacture of an engine for the planned 280-seat widebody jet, known as the C929, is a top priority.

"Only China and Russia will be the manufacturers of the engine," he said, and "will try our best to churn out a best-class engine, to support this aeroplane [project]."

China and Russia have lofty ambitions for the widebody jet, which is being designed to have a range of 12,000 kilometres.

Shanghai-based Commercial Aircraft Corporation of China (Comac) and Russian companies including aircraft assembler United Aircraft Corporation (UAC) and Rostec set up a 50-50 joint venture last year to develop the long-haul passenger plane, with deliveries targeted at beginning in 2025.

The global long-haul aero engine market is currently dominated by GE and Rolls-Royce.

China's answer to Airbus, Boeing completes Shanghai maiden flight

"We don't entirely rule out possible cooperation with GE and Rolls-Royce, but even if they were to be invited to participate in the development, it would only be at the early stage," Kladov said.

Comac's initial efforts at building a large commercial aeroplane have proved a somewhat convoluted process, after it took eight years to launch the smaller 168-seat single-aisle C919, which has a range of up to 5,556km.

The narrow-body jet made its maiden flight in early May and has yet to set a definitive time frame for deliveries.

The government has spent dozens of billions of dollars buying key components for the C919, including its engines and avionics systems, from 15 international companies including GE and Honeywell.

The narrow-body jet is aimed at challenging the Boeing 737 and Airbus A320, and was expected to take to the skies commercially by 2014.

Industry sources attributed the three-year delay in that project to Comac's unsuccessful efforts to gel with foreign suppliers.

It also took Comac seven years to get its first aircraft, the 78-seat regional jet ARJ-21 into operation after its 2008 debut flight, with its first deliveries made in 2015.

The C919 already has 570 orders from 23 foreign and domestic customers, and Comac officials predict China will require 6,865 new aircraft over the next 20 years, just over a fifth of those twin-aisle planes.

Rostec also announced it would soon sign an agreement with Aviation Industry Corp of China's general aviation subsidiary Avicopter to jointly manufacture heavy-duty helicopters.

The payload of the helicopter will be up to 15 tonnes and its service ceiling, the maximum altitude an aircraft can reach, will hit 5,700 metres.

Kladov said China has demand for at least 200 helicopters of this kind.