A global airline association is rethinking its efforts to standardize the size of carry-on luggage permitted on planes.

The International Air Transportation Association says it is pausing the rollout of its Cabin OK initiative over concerns expressed by North American airlines.

On Tuesday, industry association Airlines for America, said no U.S. airlines are supporting the smaller carry-on bag initiative recently put forth by IATA. Canadian airlines also shunned the idea.

The voluntary program would have established that smaller bags measuring 55 x 35 x 20 cm (21.5 x 13.5 x 7.5 inches) would receive a "Cabin OK" tag.

IATA says interest in the program has been "intense" but there has been confusion and concerns raised in the media and by key stakeholders.

New York Senator Chuck Schumer has criticized the effort, saying that while airlines are making record profits the change would add a further financial burden on travellers who already pay extra for checked baggage, leg room, head phones and other services.

"This is clearly an issue that is close to the heart of travellers. We need to get it right," IATA senior vice-president Tom Windmuller said in announcing a "comprehensive reassessment."

The voluntary initiative, launched June 9, was designed to bring "common sense and order" to the problem of differing bag sizes by giving passengers greater assurance their carry-on would be allowed in aircraft cabins wherever they fly. IATA insisted the guideline was not meant to set an industry standard as each airline would still decide the maximum size of carry-on luggage.

Air Canada allows carry-on luggage that is no larger than 21.5 x 15.5 x 9 inches. WestJet limits are slightly smaller at 21 x 15 x 9 inches.