MONTREAL (AFP) - The International Air Transport Association (IATA) urged governments on Thursday to take stronger action against unruly passengers on commercial flights.

The Montreal-based global airline alliance agreed at a diplomatic conference last week on changes to the Tokyo Convention of 1963, which provides the legal framework for dealing with passengers whose unruly or otherwise disruptive behaviour leads to violence or threatens flight safety.

"This agreement is good news for everybody who flies - passengers and crew alike," IATA director general and CEO Tony Tyler said in a statement.

"The changes, along with the measures already being taken by airlines, will provide an effective deterrent for unacceptable behaviour on board aircraft.

"But governments must now follow up on the success of the diplomatic conference and ratify the new protocol." About 300 incidents of unruly behaviour are reported each week.

"We urge governments to move quickly," Tyler added.

The changes, agreed at the conference attended by officials from about 100 governments, will come into force once 22 states ratify the protocol to the Tokyo Convention.

The protocol allows authorities not only in the country in which the aircraft was registered but also in the destination country to take legal action against unruly passengers.

The move closes a loophole the IATA said had allowed "many" serious offences to go unpunished.

Among the agreed changes, the protocol more clearly defines unruly behaviour - to include both the threat of or actual physical assault, or the refusal to follow safety instructions - and helps recover major costs associated with the misbehaviour.

"Unruly passengers are a very small minority," Tyler said.

"But unacceptable behaviour on board an aircraft can have serious consequences for the safety of all on board. The goal is to effectively deter such behaviour and ensure safe flights for all by making the consequences of such behaviour clear and enforceable." The aviation body has 240 members that account for 84 per cent of total air traffic worldwide.