Airbus and Boeing have a stranglehold on the market for big airliners, but other plane makers at the Paris Air Show including newcomers from Asia are targeting the lucrative segment for smaller aircraft.

Demand for regional jets, passenger planes of less than 100 seats, has risen in line with the market for large commercial aircraft as the booming global economy continues to boost the travel industry.

Small jet makers Bombardier from Canada and Embraer from Brazil have reaped the benefits, thriving in a part of the aircraft business neglected by the powerful duo of Airbus and Boeing.

There are signs, however, that competition is about to hot up.

A consortium of Chinese companies and research institutes have been working on a Chinese regional jet, the ARJ21, which is set to begin flights next year.

Earlier this week, the China Aviation Industry Corporation, the state company in charge of the project, signed a cooperation deal with Bombardier to extend its range of planes.

The Canadian group is to invest 100 million dollars (74 million euros) in the development of a ARJ21-900, a stretched version of the ARJ21, and the two companies have pledged to share technical information.

Japan's Mitsubishi Heavy Industries is also in Paris, touting its MRJ, the Mitsubishi Regional Jet, which it hopes to put into production at the beginning of next year.

Visitors to the company's stand are invited to visit a replica of the cabin, which features cream-coloured, slim leather seats, two either side of the central aisle.

The company will make a decision about whether to launch the jet in the first half of next year after consultations with partners.

"We are talking to suppliers and potential customers and the impression so far is good," a spokesman for the programme told AFP.

Mitsubishi Heavy Industries believes there is a market for 5,000 regional jets of 70-90 seats in the next 20 years, which tallies with predictions by analysts.

The MRJ is not a foray into a unknown market: the company is a key subcontractor for Boeing, making fuselage and wing parts for a host of the US company's large jets.

"We have lots of manufacturing experience but not a whole plane," said the spokesman.

The MRJ would be the only Japanese commercial plane in production if launched.

The only Japanese airliner to be built after World War II was the JS-11, but manufacturing ended in 1974.

Mitsubishi is in talks with Boeing on an agreement covering cooperation in areas such as marketing and maintenance for the MRJ.

Japanese newspaper Nikkei claimed Wednesday that the two companies had signed a deal, but a Boeing spokesman told AFP that the companies had merely agreed to "continue our studies."

There was no timetable for a deal, he said.

Russia's aerospace giant Sukhoi is also eyeing the market for regional jets and is hoping a first deal to supply its aircraft, the Superjet 100, to a non-Russian client will boost its profile.

Sukhoi announced on Tuesday that small low-cost airliner ItAli had become its first foreign client with an order for 10 Superjet 100s with options for 10 more.

"Between now and 2024, Sukhoi expects to sell 800 Superjet 100s, including 300 in Russia and 500 on the Western market," said the head of commercial plane operations for the Russian group, Victor Subbotin.

The first deliveries of the Superjet 100 to Russian clients are scheduled for 2008.

For the time being, none of the five companies in the regional jet business is able to challenge Airbus or Boeing in the market for big commercial aircraft.

This may change in the future, however, as Chinese ambition does not stop with the ARJ21.

Beijing has said it wants a domestic aerospace industry capable of building airliners.