Tensions continue to rise over the European Union 's decision to include aviation in its Emissions Trading System (EU ETS), with some governments threatening to boycott the carbon emissions tax altogether. Here is a run down of how the row has played out over the last few weeks:
7 Dec 2010 - Senator John Thune (pictured) proposes legislation that would ban American carriers from participation in the ETS - in violation of EU law.
20 Dec - The US Department of Transportation announces it is formally seeking data from both US and European carriers to bolster its argument that the ETS is illegal.
1 Jan 2012 - Airlines operating flights within Europe become subject to the EU ETS. They will be expected to surrender allowances for their 2012 carbon emissions in April 2013.
4 Jan - Delta reveals it has introduced a $3 surcharge on European flights, effective as of 2 January. Its spokesperson refuses to confirm that this is to directly offset the cost of the ETS.
Chinese airlines announce they are not going to comply with the ETS. The European Commission responds by pointing out that an operating ban could be imposed on any airline to persistently break EU law.
5 Jan - United introduces a $3 surcharge on European flights.
6 Jan - American Airlines and US Airways confirm similar surcharges.
9 Jan - An OAG report forecasts two scenarios: either passenger fares will rise by an average of 3% or airlines will use non-EU points as intermediate stops to avoid the additional costs.
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