The European Union has called on member states to agree a common energy policy, amid fierce national protectionism and concerns about "serious malfunctions" in the way the markets currently work.

Brussels' Energy Commissioner, Andris Piebalgs, said: "The completion of the internal market, the fight against climate change, and security of supply, are common energy challenges that call for common solutions. It is time for a new European energy policy."

Less than a month after promising to clamp down on alleged anti-competitive practices operated by some of the continent's major energy companies, the European Commission today set out six priority areas.

These include a European energy regulator - whose powers would supercede those of British watchdog Ofgem - prioritising an "interconnection" plan for the European network, and taking concrete steps to ensure a level playing field among providers.

"The energy challenges of the 21st century require a common EU response. The EU is an essential element in delivering sustainable, competitive and secure energy for European citizens," Commission president Jose Manuel Barroso said.

"A common approach, articulated with a common voice, will enable Europe to lead the search for energy solutions," he said.

The Commission delivered its call as it published a Green Paper setting out more than 20 proposals for an EU-wide policy. It said the Green Paper was designed to meet its three "core objectives" of "sustainable development, competitiveness, and security of supply".

As it invited comments from member states, the Commission said it would table "concrete proposals" by the end of the year.

Brussels' second intervention in the fragmented European energy markets comes amid heightened security fears about energy interruption across all members of the EU states, particularly following the high-profile spat between Ukraine and Russia that had an immediate knock-on effect on the European energy pipeline.

It also comes as a rash of recent cross-border European energy mergers has prompted individual territories to scramble to protect their national interests.

Most recently, the proposed merger in France of gas companies Gaz de France and Suez sparked outrage in Italy, where domestic-headquartered group Enel had been hoping to launch a Suez takeover.

British Gas owner Centrica has already expressed concerns about the deal, amid concerns that a post-merger gas giant would have a stranglehold on European supply. Companies and regulators in Brussels have voiced worries about the takeover.

In Spain, domestic utilities Gas Natural and Endesa are in the thick of a near £30 billion takeover tussle, amid rival interest from E.On of Germany.