The European Commission is to review Member States’ intergovernmental oil and gas deals before they are signed.
The change is an important part of the sustainable energy security package proposed in February 2016.
EU Member States will not be able to sign prospective oil and gas deals until they have been reviewed by the Commission and received feedback, which must be taken into account.
It is hoped this will increase transparency in the gas market, make sure all intergovernmental agreements are in line with EU law and strengthen the resilience of the region to supply disruptions.
The Commission said the rule change is a major political achievement and was confirmed in record time, coming only nine months after its initial proposal.
It will help ensure energy security, a vital cornerstone of the Energy Union Strategy, it adds.
Miguel Arias Cañete, Commissioner for Climate Action and Energy, said: “The new rules, agreed by the negotiators of the European Parliament and the Council, will allow the Commission to guarantee that no energy deal jeopardises the security of supply in an EU country or hampers the functioning of the EU’s energy market.”
Electricity deals between Member States and non-EU nations could also be included under the rule in the future.