The concerted opposition to the European Union's push toward forcing foreign airlines landing in Europe to become a part of its emissions trading scheme has led to an unexpected development, whose implications extend to setting the global climate agenda.

The United States, which had so far rejected the scheme, now wants to resolve the trade dispute, by suggesting a global cap and trade regime. It is included among the options being considered by the International Civil Aviation Organization Council, which last month also dropped consideration of an emissions trading system.

The US, and EU, policy shift comes immediately after the Rio+20 Conference where the principle of common but differentiated responsibilities was re-affirmed, whereas the fundamental principle underpinning ICAO is that all aircraft operators are treated equally regardless of their country of origin.