NAPs are the cornerstone of the EU's efforts to fight climate change and meet emissions reduction goals under the Kyoto Protocol, outlining how much CO2 industries in each EU country may emit in a given period.

The Commission had now officially received 10 national plans, EU Environment Commissioner Stavros Dimas said.

"The Commission appreciates very much the national efforts and the national plans," he told the European Parliament. "Those countries that are still hesitating are being sent reminders."

"If member states do not present their reports as requested, the Commission may well undertake other steps," he said, hinting at legal action. "I hope that this will not be necessary -- I hope that in the coming months the failing member states will present the statistics that we require of them."

In the first phase of the EU scheme, companies had overestimated their likely emissions, and EU governments were then "complacent in accepting their figures", Dimas said.

"I am personally going to be tough but fair with the member states regarding the national allocation plans," Dimas said.

Energy traders say the leisurely NAP submissions by EU states risks injecting confusion into pricing carbon allowances.

The carbon market affects European power markets because the higher the carbon price, the more expensive it is to burn fossil fuels, pushing up power prices.

Earlier on Tuesday, Finland said it intended to submit its second-phase plan in early October. Spain, one of the poorest performers on greenhouse gas controls among rich nations, said on Monday it would submit its NAP in the next two months.

The EU trading scheme works by giving heavy industry a certain quota of carbon credits allowing them to emit heat-trapping carbon dioxide up to a certain limit.

If they undercut the limit they can sell the credits surplus, and if they exceed it they have to buy more.