And from the corporate sector, seven companies involved in aviation have written to European governments complaining about the recent inclusion of plane emissions in the EU Emission Trading Scheme (ETS).

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They'll be talking about what needs to be done to ensure that an adequate proposal goes on the table at the next UN climate summit, in Qatar in December, for putting EU emission cuts (and possibly others too) under the Kyoto Protocol.

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The new rule, which came into force in January, means that all airlines have to add up greenhouse gas emissions from flights that begin or end at EU airports, and must pay a small charge, or trade carbon permits on the EU emission trading scheme, if they exceed their allowance.

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Creating a new fund within the EU's Emission Trading Scheme (EUETS), which would give firms valuable carbon credits for every stored tonne of CO2.

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Climate Change Minister Stewart Stevenson said it was important to continue to pressure the EU to increase co2 emission targets.

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Under the agreement the EU will place its current emission-cutting pledges inside the legally-binding Kyoto Protocol, a key demand of developing countries.

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Poland says the EU's distribution of CO2 emission permits is unfair because it uses gas-based benchmarks.

BBC: EU court rebuffs Poland over CO2 emissions

If more countries introduce contracts for carbon-emission quotas compatible with those traded in the EU (which use a unit called the European Union Allowance), the result could be a single worldwide market one day.

ECONOMIST: Buttonwood

The EU's Emissions Trading System (ETS) created a market in CO2 emission allowances, meaning that heavy emitters of CO2 have to buy allowances from enterprises that have managed to cut their CO2 emissions.

BBC: EU court rebuffs Poland over CO2 emissions