International airlines are aiming to take at least 10 per cent of their fuel from synthetic or biofuel sources within a decade.

The International Air Transport Association (IATA) set the "synfuel" target at its latest board meeting as part of a program to address rising fuel costs and increasing criticism about the industry's environmental impact. IATA says there are hopes a synthetic jet fuel meeting all current specifications will be approved by the end of this year.

Engine manufacturers are seeking fuel with a high energy content that is also able to be used by engines without a major redesign.

They are looking at both biofuels and synthetic fuels such as those derived from the coal-based, Fischer-Tropsch process.

Biofuels have the advantage of low-emission levels but they can have a lower energy content than Jet A1.

They can also require vast tracts of land to produce a relatively small amount of fuel.

The FT process, where coal is turned into gas and ultimately a liquid, has the advantages of a plentiful supply of raw materials as well as compatibility with current engines and infrastructure.

But it does not notably reduce carbon dioxide emissions.South African-based Sasol is among a handful of companies that have commercialised FT technology and has been producing semi-synthetic fuels - a 50/50 mix with normal petroleum fuel - for aviation.

According to IATA, major aircraft engine manufacturers are now in the final stages of testing a fully synthetic jet fuel but experts believe it will take more co-operation and research to produce a finished product. IATA director general Giovanni Bisignani told The Australian a team in Montreal had started to work with the engine manufacturers and oil companies on developing alternative fuels.

With the industry facing a fuel bill this year of $US115 billion (AU$153 billion), Mr Bisignani said a replacement needed to be cheaper and produce less carbon dioxide.

He called on the oil companies, which are currently slugging airlines for higher refinery margins, to contribute to the research.

The IATA boss had earlier told an Aerospace Forum Asia lunch in Hong Kong that the industry had not been able to effectively market environmental achievements such as significant reductions in aircraft emissions and noise.

"We represent 8 per cent of the GDP and are responsible for just 2 per cent of C02," he said.

"Can you show me a highway car that's more fuel efficient than planes, especially the new planes which will have a consumption of less than 3 litres per 100km per passenger?"

Mr Bisignani also warned against adopting carbon emission trading schemes on a piecemeal basis.

He warned that the introduction of different trading schemes in different parts of the world "will be a mess and it will not be positive for the environment".

"This is a global industry, it needs global standards," he said.

"We cannot start having an emission trading scheme that's different in different parts of the world," he said.

"In Europe we've been able to stop this approach by saying let's give the responsibility to ICAO. That's the United Nations specialised agency for this and as you know, ICAO will be discussing this at the next assembly."