The European Commission has received five national plans for curbing carbon dioxide emissions, part of the 15-nation bloc's scheme to meet commitments made under the Kyoto Protocol.
"We had five notified plans as of midnight. But we know there are others in the pipeline - it's a question of when they will arrive and we know that all of them are on their way," Ewa Hedlund, the Commission's environment spokeswoman, told journalists.
The countries that had notified their plans by the Commission's deadline of midnight (2200 GMT) on March 31 were Austria, Denmark, Finland, Germany and Ireland, she said.
EU governments must submit plans for distributing CO2 credits in their countries as part of the EU's pioneering emissions trading scheme (ETS) to start in January 2005.
ETS is a central element of the EU's bid to meet climate change targets under the Kyoto Protocol to reduce the greenhouse gas emissions that scientists say cause global warming.
However, the Commission will not know until next week whether all 15 countries have complied with the deadline as the time of a postmark is also valid.
This means that if a country can prove its plan was sent before the deadline, it will escape a Commission "infringement letter", a first warning of impending legal action.
All countries were still expected to send in their plans and none had requested extra time, Hedlund said.
"They're all working on the plans, we've known that all the time. The ones that have made them public, we know they're very close," she said, citing Britain, Portugal and the Netherlands.
"We will get them very soon. We are expecting all of them, there is no country that says they will not do it," she said.
"We have to see when we actually get them all in and look into
the reason for the delay."