European energy ministers agreed an overhaul of 40-year-old rules on oil stocks on Friday after watering down proposals to improve transparency by publishing weekly data on stock levels, Reuters reported.
Instead, European Union countries will circulate monthly stocks information and align the reporting system with that of the International Energy Agency (IEA).
Total oil stocks must equal at least 90 days of average imports or 61 days of average consumption, and one third must be quickly available as oil products fine-tuned to the country`s particular consumption needs.
Those stocks of products must be owned or easily controlled by the government.
Monthly reporting of stock levels is a small change from the current system under which EU states must confirm each month whether they hold 90 days-stocks, but need provide no more detail.
"Whilst the Council did not retain some elements of our original proposal, I`m satisfied the new legislation will...minimise the negative effects on consumers in case of a supply crisis," said Energy Commissioner Andris Piebalgs.
EU member states have called for tough new measures to bolster energy security after the bloc drifted into heavy dependence on Russian energy supplies over the last few decades.
This has led to repeated shocks when Moscow cut flows of gas through Ukraine and oil through Belarus in recent years.
But European Commission proposals aimed at increasing transparency via weekly reports and at increasing its control over the release of oil stocks during crises have met hostility from some energy ministers.
Last minute wrangling led to a deal under which member states are obliged to act when the Commission recommends they release stocks during emergencies -- but the language of the legislation was weak by EU standards.
"It is appropriate for member states to respond positively to such Commission recommendations in the interest of strong EU-wide solidarity and cohesion," said the carefully-worded legal text.
The new laws must be applied by 2013 at the latest.
The original directive was made in 1968 and strengthened at the time of the first major oil shock in 1973.
But since 1973, the EU has moved from six to 27 member states and its oil needs have changed, with demand soaring for jet fuel and waning for heating oil -- hence the need for revision.